If three angles of a quadrilateral are each equal to 75°, the fourth angle is
A. 150°
B. 135°
C. 45°
D. 75°
Let the fourth angle be x
Since the sum of interior angles of a Quadrilateral is 3600
x + 3×750 = 3600
⇒ x = 3600 – 2250
⇒ x = 1350
For which of the following, diagonals bisect each other?
A. square
B. kite
C. trapezium
D. quadrilateral
In a square the diagonals bisect each other because both the opposite side pairs of a square are parallel. But in a trapezium only one pair of opposite pair are parallel. In a kite no opposite pairs are parallel.
For which of the following figures, all angles are equal?
A. rectangle
B. kite
C. trapezium
D. rhombus
In a rectangle all the angles are at right angle and hence they are all equal. But in a kite trapezium or rhombus all the angles are not right angles hence not equal.
For which of the following figures, diagonals are perpendicular to each other?
A. parallelogram
B. kite
C. trapezium
D. rectangle
In a Kite one pair of opposite angles are at right angles and the adjacent sides are equal. So their diagonals are perpendicular. But in a trapezium, parallelogram or rectangle it doesn’t happen.
For which of the following figures, diagonals are equal?
A. trapezium
B. rhombus
C. parallelogram
D. rectangle
In a rectangle since all the four angles are equal hence the diagonals are equal. But in a trapezium, parallelogram or rhombus all the angles are not equal hence their diagonals are unequal.
Which of the following figures satisfy the following properties?
- All sides are congruent.
- All angles are right angles.
- Opposite sides are parallel.
A.
B.
C.
D.
Option:(c)
R is a square. In a square all sides are equal, all angles are equal and at right angles and also opposite sides are parallel. P,Q,S are a trapezium, parallelogram and rectangle respectively whose all sides are not equal.
Which of the following figures satisfy the following property?
- Has two pairs of congruent adjacent sides.
A.
B.
C.
D.
R is a kite whose adjacent sides are equal. P ,Q & S are a trapezium ,parallelogram and rectangle respectively whose adjacent sides are unequal.
Which of the following figures satisfy the following property?
- Only one pair of sides are parallel.
A.
B.
C.
D.
P is a trapezium and has only one pair of parallel side. Q,R,S is a parallelogram ,square and rectangle respectively which has two pair of parallel side.
Which of the following figures do not satisfy any of the following properties?
- All sides are equal.
- All angles are right angles.
- Opposite sides are parallel.
A.
B.
C.
D.
Q is a square. In a square all sides are equal, all angles are equal and at right angles and also opposite sides are parallel. P,S,R are a trapezium, parallelogram and rectangle respectively whose all sides are not equal.
Which of the following properties describe a trapezium?
(A) A pair of opposite side is parallel.
(B) The diagonals bisect each other.
(C) The diagonals are perpendicular to each other.
(D) The diagonals are equal.
Option: (A)
A trapezium is a quadrilateral which has only one pair of sides which are parallel. The other properties are not true for trapezium.
Which of the following is a property of a parallelogram?
A. Opposite sides are parallel.
B. The diagonals bisect each other at right angles.
C. The diagonals are perpendicular to each other.
D. All angles are equal.
In a parallelogram the opposite sides are parallel. The other properties are not true.
Which is the maximum number of obtuse angle that a quadrilateral can have?
A. 1
B. 2
C. 3
D. 4
Sum of interior angles of a quadrilateral is 3600. An obtuse angle is an angle between 900 and 1800 .So all the angles can’t be obtuse since then the sum will exceed 3600.So maximum it can have 3 obtuse angle.
How many non-overlapping triangles can we make in a n-gon (polygon having n sides), by joining the vertices?
A. n-1
B. n-2
C. n-3
D. n-4
There can be n-1 lines that can be drawn from one vertices. Out of these 2 sides are adjacent sides so n-3 lines can be drawn. When a n-gon is divided by n-3 lines the n-gon is divided into n-2 triangles.
What is the sum of the angles of a pentagon?
A. 180°
B. 360°
C. 540°
(d)720°
Sum of interior angles of a polygon = (2n-4)×900 where n represents the number of sides of a polygon
In this problem n = 5
⇒ Sum of interior angles = (10-4) ×900
⇒ Sum of interior angles = 5400
What is the sum of the angles of a hexagon?
A. 180°
B. 360°
C. 540°
(d)720°
Sum of interior angles of a polygon = (2n-4)×900 where n represents the number of sides of a polygon
In this problem n = 6
⇒ Sum of interior angles = (12-4) ×900
⇒ Sum of interior angles = 7200
If two adjacent angles of a parallelogram are (5x-5)° and (10x + 35)°, then the ratio of these angles is
A. 1:3
B. 2:3
C. 1:4
D. 1:2
Adjacent angles of a parallelogram are supplementary
5x-5 + 10x + 35 = 180
⇒ 15 x + 30 = 180
⇒ 15x = 150
⇒ x = 10
⇒ 5x-5 = 450
⇒ 10x + 35 = 1350
⇒ Ratio = 1:3
A quadrilateral whose all sides are equal, opposite angles are equal and the diagonals bisect each other at right angles is a ______.
A. rhombus
B. parallelogram
C. square
D. rectangle
All sides of a rhombus are equal and the diagonals bisect each other at right angles. It is also applicable for square but it is a superior form of rhombus whose all angles are equal.
A quadrilateral whose opposite sides and all angles are equal is a
A. rectangle
B. parallelogram
C. square
D. rhombus
A rectangle is a quadrilateral whose opposite sides and all angles are equal. It is also applicable for square but it is a superior form of rectangle whose all sides are equal.
A quadrilateral whose all sides, diagonals and angles are equal is a
A. square
B. trapezium
C. rectangle
D. rhombus
A square is the only quadrilateral whose all sides, diagonals and angles are equal.
How many diagonals does a hexagon have?
A. 9
B. 8
C. 2
D. 6
Number of diagonals of a polygon =
where n is the number of sides
Here n = 6
So the number of diagonals =
If the adjacent sides of the parallelogram are equal then parallelogram is a
A. rectangle
B. trapezium
C. rhombus
D. square
In parallelogram the opposite sides are equal. When the adjacent sides becomes equal all the sides of the parallelogram becomes equal and hence it becomes a rhombus.
If the diagonals of the quadrilateral are equal and bisect each other, then the quadrilateral is a
A. rhombus
B. rectangle
C. square
D. parallelogram
A rectangle is a quadrilateral whose diagonals are equal and bisect each other. It is also applicable for square but it is a superior form of rectangle whose all sides are equal.
The sum of all exterior angles of a triangle is
A. 180°
B. 360°
C. 540°
(d)720°
The sum of all exterior angles of all polygons is equal to 3600
Which of the following is an equiangular and equilateral polygon?
A. square
B. rectangle
C. rhombus
D. right triangle
A square is the only polygon whose all sides and all angles are equal.
Which one has all the properties of a kite and a parallelogram?
A. trapezium
B. rhombus
C. rectangle
D. parallelogram
In a rhombus the opposite sides are parallel, diagonals bisect at right angles and all the sides are equal. So it has all the properties of a kite and a parallelogram.
The angles of the quadrilaterals are in the ratio 1:2:3:4, the smallest angle is
A. 72°
B. 144°
C. 36°
D. 18°
Let the angles be x ,2x ,3x ,4x
Sum of interior angles of a quadrilateral = 3600
x + 2x + 3x + 4x = 3600
⇒ 10x = 3600
⇒ x = 360
In the trapezium ABCD, the measure of ∠D is
A. 55°
B. 115°
C. 135°
D. 125°
D & A are supplementary
D + A = 1800
⇒ D = 1800-550
⇒ D = 1350
A quadrilateral has three acute angles. If each measures 80°, the measure of the fourth angle is
A. 150°
B. 120°
C. 105°
D. 140°
Let the fourth angle be x
Sum of interior angles of a quadrilateral = 3600
x + 80× 3 = 3600
⇒ x = 3600-2400
⇒ x = 1200
The number of sides of a regular polygon where each exterior angle has a measure of 45° is
A. 8
B. 10
C. 4
D. 6
Let the number of sides be n
sum of all exterior angles of all polygons is equal to 3600
n× 450 = 3600
⇒ n = 8
In a parallelogram PQRS, if ∠p= 60°, then other three angles are
A. 45°, 135°, 120°
B. 60°, 120°, 120°
C. 60°, 135°, 135°
D. 45°, 135°, 135°
Opposite angles are equal and adjacent angles are supplementary in a parallelogram.
P = 60°
⇒ R = 60°
Q = ∠S = 1800- 60°
Q = ∠S = 1200
The three angles are 60°, 120°, 120°
If two angles of the parallelogram are in the ratio 2:3, then the measure of angles are
A. 72°, 108°
B. 36°, 54°
C. 80°, 120°
D. 96°, 144°
Let the angles be 2x, 3x
The adjacent angles of a parallelogram are always supplementary and the opposite angles are always equal
2x + 3x = 1800
⇒ 5x = 1800
⇒ x = 360
So, the angles are
2× 36 = 720
3× 36 = 1080
If PQRS is a parallelogram, then P - R is equal to
A. 60°
B. 90°
C. 80°
D. 0°
The opposite angles of a parallelogram are always equal and so their difference is always 00
The sum of the adjacent angles of a parallelogram is
A. 180°
B. 120°
C. 360°
D. 90°
The adjacent angles of a parallelogram are always supplementary so sum is 1800
The angle between the two altitudes of a parallelogram through the same vertex of an obtuse angle of the parallelogram is 30°. The measure of the obtuse angle is
A. 100°
B. 150°
C. 105°
D. 120°
BE & EF are perpendiculars from the same point
∠ EBF = 300(given)
Sum of interior angles of a quadrilateral = 3600
∠ EBF + ∠ BED + ∠ EDF + ∠ DFB = 3600
∠ EDF = 3600-(900 + 900 + 300)
∠ EDF = 1500 which is an obtuse angle.
In the given figure, ABCD and BCDE are parallelograms with common base DC. If BC BD, then ∠BEC=
A. 60°
B. 30°
C. 150°
D. 120°
∠ BAC = 300 (Given)
∠ ABC = 1500(Supplementary angles)
∠ ABD = 1500-900 = 600
∠ BDC = 600(Co interior angles)
∠ BEC = 600(Opposite angles)
Length of one of the diagonals of a rectangle whose sides are 10 cm and 24 cm is
A. 25cm
B. 20cm
C. 26cm
D. 3.5cm
By using Pythagoras theorem:
Length of diagonal = √ (102 + 242)
⇒ Length of diagonal = √676
⇒ Length of diagonal = 26cm
If the adjacent angles of a parallelogram are equal, then the parallelogram is a
A. rectangle
B. trapezium
C. rhombus
D. any of the three
In parallelogram the opposite angles are equal. When the adjacent angles become equal all the angles become equal and so it becomes a rectangle.
Which of the following can be four interior angles of a quadrilateral?
A. 140°, 40°, 20°, 160°
B. 270°, 150°, 30°, 20°
C. 40°, 70°, 90°, 60°
D. 110°, 40°, 30°, 180°
Sum of interior angles of a quadrilateral = 3600
In option (a) & (d) this condition is true. But in option (d) one angle is 1800 which if considered correct the quadrilateral becomes a triangle.
The sum of angles of a concave quadrilateral is
A. more than 360°
B. less than 360°
C. equal to 360°
D. twice of 360°
Sum of interior angles of a quadrilateral = 3600 for both concave and convex quadrilateral.
Which of the following can never be the measure of exterior angle of a regular polygon?
A. 22°
B. 36°
C. 45°
D. 30°
Sum of exterior angles of a polygon = 3600
3600 divided by any one of the angles must be a whole number since it gives the number of sides.
But when 3600 is divided by option (a) it gives a fraction which can be the number of sides of a polygon.
In the figure, BEST is a rhombus. Then the value of y-x is
A. 40°
B. 50°
C. 20°
D. 10°
BEST is a rhombus,
So, TS || BS
∠SBE = ∠BST = 40° (alternate interior angles)
As Diagonals of a rhombus bisect at right angles.
∠y = 90°
In Δ TSO,
∠STO + ∠OST = ∠EOS (Exterior angle property)
⇒ x + 40° = 90°
⇒ x = 90° - 40°
⇒ x = 50°
So, y - x = 90° -50°
= 40°
The closed curve which a polygon is also is
A.
B.
C.
D.
Only in (a) the line segments don’t intersect each other where as in the others it does.
Which of the following is not true for an exterior angle of a regular polygon with n sides?
A. Each exterior angle =
B. Exterior angle = 180° - interior angle
C. n =
D. Each exterior angle =
The last option is wrong because each exterior angle
=
PQRS is a square. PR and SQ intersect at O. Then POQ is a
A. right angle
B. straight angle
C. reflex angle
D. complete angle
A square is a special type of rhombus whose all the angles are equal. We know that diagonals of a rhombus bisect at right angles so this is also true for a square.
Two adjacent angles of a parallelogram are in the ratio 1:5. Then all the angles of the parallelogram are
A. 30°, 150°, 30°,150°
B. 85°, 95°, 85°, 95°
C. 45°, 135°, 45°, 135°
D. 30°, 180°, 30°, 180°
Let the angles be x and 5x
The adjacent angles of a parallelogram are supplementary
x + 5x = 1800
6x = 1800
⇒ x = 300
So the angles are 30°, 150°, 30°,150°
A parallelogram PQRS is constructed with sides QR = 6cm. PQ = 4cm and PQR = 90°. Then PQRS is a
A. square
B. rectangle
C. rhombus
D. trapezium
In a rectangle the adjacent sides are unequal and the angle between two sides is 900.So the given parallelogram is a rectangle.
The angles P, Q, R and S of a quadrilateral are in the ratio 1:3:7:9. Then PQRS is a
A. parallelogram
B. trapezium with PQRS
C. trapezium with QRPS
D. kite
Given: Angles of a quadrilateral are in the ratio 1: 3: 7: 9
Formula Used: Sum of the angles of a quadrilateral = 3600
Let the angles be x, 3x, 7x, and 9x
Adding the angles we get,
x + 3x + 7x + 9x = 3600
⇒ 20x = 3600
⇒ x = 180
So, we have,Angles P, Q, R and S = 180, 540, 1260 & 1620
∠ P ,∠S & ∠Q, ∠R are supplementary
So, PQ ||RS and it’s a trapezium
PQRS is a trapezium in which PQSR and P = 130°, Q = 110°, then R is equal to :
A. 70°
B. 50°
C. 65°
D. 55°
In a trapezium the adjacent angles in the non-parallel sides are supplementary
∠ R + ∠ Q = 1800
⇒ ∠ R = 1800-1100
⇒ ∠ R = 700
The number of sides of a regular polygon who’s each interior angle is of 135° is
A. 6
B. 7
C. 8
D. 9
Each interior angle = 1350
Let the number of sides be n
Sum of interior angles = n×1350
Sum of interior angles is given by = (2n-4) × 900
Equating we get
(2n-4)90 = 135n
⇒ 180n-360 = 135n
⇒ 45n = 360
⇒ n = 8
If a diagonal of a quadrilateral bisects both the angles, then it is a
A. kite
B. parallelogram
C. rhombus
D. rectangle
A parallelogram is a quadrilateral whose diagonal bisects both the angles. It is also true for rhombus and rectangle but in a rhombus all the sides are also equal and in a rectangle all the angles are also equal.
To construct a unique parallelogram, the minimum number of measurements required is
A. 2
B. 3
C. 4
D. 5
In a parallelogram the opposite sides and opposite angles are equal. So to construct a parallelogram we need the measurements of the two adjacent sides of the parallelogram and the angle between them.
To construct a unique rectangle, the minimum number of measurements required is
A. 4
B. 3
C. 2
D. 1
We only need the measurement of the length and the breadth of a rectangle to construct it. So only two measurements are required.
Fill in the blanks to make the statements true.
In quadrilateral HOPE, the pairs of opposite sides are____
HO ,PE & HE ,OP
HO ,PE & HE ,OP are the opposite sides because they have no common vertices.
Fill in the blanks to make the statements true.
In quadrilateral ROPE, the pairs of adjacent angles are______
∠R , ∠O; ∠O, ∠P; ∠P, ∠E; ∠E, ∠R
∠R , ∠O; ∠O, ∠P; ∠P, ∠E; ∠E, ∠R are the pair of adjacent angles because they have a common vertices.
Fill in the blanks to make the statements true.
In quadrilateral WXYZ, the pairs of opposite angles are___
∠W , ∠Y ; ∠X , ∠Z
∠W , ∠Y ; ∠X , ∠Z are the pair of opposite angles because they have no common sides.
Fill in the blanks to make the statements true.
The diagonals of the quadrilateral DEFG are ______ and _______.
DF & EG
DF & EG are the opposite vertices of the quadrilateral and hence they create two diagonals.
Fill in the blanks to make the statements true.
The sum of all _______ of a quadrilateral is 360°.
Angles
Sum of both interior as well as exterior angles of a quadrilateral is 360°.
Fill in the blanks to make the statements true.
The measure of each exterior angle of a regular pentagon is ________.
720
Each exterior angle =
where n is the number of sides
For this problem n = 5 and so each exterior angle = 720
Fill in the blanks to make the statements true.
Sum of the angles of a hexagon is _______.
7200
Sum of interior angle = (2n-4)×900
where n is the number of sides
In this problem n = 6
(12-4) × 900
= 8×900 = 7200
Fill in the blanks to make the statements true.
The measure of each exterior angle of a regular polygon of 18 sides is ________.
200
Each exterior angle =
where n is the number of sides
For this problem n = 18
and so each exterior angle = 200
The number of sides of regular polygon, where each exterior angle has a measure of 36° is _______.
n× Each exterior angle = 3600
where n is the number of sides
For this problem each exterior angle = 360
n =
⇒ n = 10
Fill in the blanks to make the statements true.
is a closed curve entirely made up of the line segments. The another name for this shape is __________.
Concave Polygon
The polygon has more than one reflex angle .So it is a concave polygon.
Fill in the blanks to make the statements true.
A quadrilateral that is not a parallelogram but has exactly two opposite angles of equal measure is _________.
Kite
One pair of opposite angles are equal but the other pair of angle is not equal in a kite.
Fill in the blanks to make the statements true.
The measure of each angle of regular pentagon is _________.
1080
Sum of interior angle = (2n-4) × 900
where n is the number of sides
In this problem n = 5
(10-4) × 900
= 6×900 = 5400
Each interior angle =
⇒ Each interior angle = 1080
Fill in the blanks to make the statements true.
The name of three-sided regular polygon is _______.
Equilateral triangle
Equilateral triangle is a three-sided regular polygon.
Fill in the blanks to make the statements true.
The number of diagonals in a hexagon is ______.
9
Number of diagonals of a polygon =
where n is the number of sides
Here n = 6
So the number of diagonals =
Fill in the blanks to make the statements true.
A polygon is a simplest closed curve made up of only ________.
Line segments
A polygon is a simplest closed curve made up of only line segments which don’t intersect with each other.
Fill in the blanks to make the statements true.
A regular polygon is a polygon whose all sides are equal and all _____ are equal.
angles
All the sides as well as angles are equal for regular polygon.
Fill in the blanks to make the statements true.
The sum of interior angles of a polygon of n sides is ______ right angles.
2n-4
Sum of interior angle = (2n-4)×900
So Sum of interior angles is 2n-4 right angles
Fill in the blanks to make the statements true.
The sum of all exterior angles of a polygon is _______.
3600
The sum of all exterior angles of any polygon is always 3600
Fill in the blanks to make the statements true.
_______ is a regular quadrilateral.
Square
All the angles and sides of square are equal. So it is a regular quadrilateral
Fill in the blanks to make the statements true.
A quadrilateral in which a pair of opposite sides is parallel is _____.
Trapezium
Trapezium is a in which a pair of opposite sides is parallel .
Fill in the blanks to make the statements true.
If all sides of a quadrilateral are equal, it is a ________.
Rhombus
Rhombus is a quadrilateral whose all sides are equal.
Fill in the blanks to make the statements true.
In a rhombus diagonal intersect at _______ angles.
Right
Since all sides are equal in a rhombus so they intersect at right angles.
Fill in the blanks to make the statements true.
_______ measurements can determine a quadrilateral uniquely.
Five
We need 5 measurements to determine a quadrilateral uniquely. It can be four sides one angle or 3 sides and 2 included angle.
Fill in the blanks to make the statements true.
A quadrilateral can be constructed uniquely if its three sides and ______ angles are given.
Two included
We need 5 measurements to determine a quadrilateral uniquely. It can be drawn uniquely if its three sides and two included angles are given.
Fill in the blanks to make the statements true.
A rhombus is a parallelogram in which _______ sides are equal.
All
rhombus is a parallelogram in which all the sides are equal and the diagonals bisect at right angle.
Fill in the blanks to make the statements true.
The measure of ____ angle of concave quadrilateral is more than 180°.
One
A concave polygon has one reflex angle which is greater than 1800
Fill in the blanks to make the statements true.
A diagonal of a quadrilateral is a line segment that joins two _______ vertices of the quadrilateral.
Opposite
Diagonals are drawn by joining two opposite vertices of a quadrilateral.
Fill in the blanks to make the statements true.
The number of sides in a regular polygon having measure of an exterior angle as 72° is _______.
5
Number of sides × each exterior angle = 3600
So number of sides =
⇒ Number of sides = 5
Fill in the blanks to make the statements true.
If the diagonals of a quadrilateral bisect each other, it is a ________.
Parallelogram
The diagonals of a parallelogram always bisects each other.
Fill in the blanks to make the statements true.
The adjacent sides of a parallelogram are 5cm and 9cm. It's perimeter is ________.
28cm
Perimeter of parallelogram = 2× (Sum of adjacent sides)
⇒ 2×14 = 28cm
Fill in the blanks to make the statements true.
A nonagon has _______ sides.
9
Nonagon is a polygon having 9 sides.
Fill in the blanks to make the statements true.
Diagonals of a rectangle are _________.
Equal
Diagonals of a rectangle are always equal in magnitude.
Fill in the blanks to make the statements true.
A polygon having 10 sides known as _________.
Decagon
Decagon is a polygon having 10 sides.
Fill in the blanks to make the statements true.
A rectangle whose adjacent sides are equal becomes a ________.
Square
If the adjacent sides of rectangle becomes equal then all the sides of the rectangle becomes equal and hence it becomes a square.
Fill in the blanks to make the statements true.
If one diagonal of a rectangle is 6cm long, length of the other diagonal is _______.
6cm
The diagonals of a rectangle are always equal in magnitude.
Fill in the blanks to make the statements true.
Adjacent angles of a parallelogram are _____.
Supplementary
Adjacent angles of a parallelogram always add up to 1800
Fill in the blanks to make the statements true.
If only one diagonal of a quadrilateral bisects the other, then the quadrilateral is known as _______.
Kite
Only one diagonal of a kite bisects each other and the diagonals meet at right angle.
Fill in the blanks to make the statements true.
The trapezium ABCD with ABCD, if ∠A = 1000, then ∠D =
800
The adjacent angles of non-parallel sides are supplementary
∠ A + ∠D = 1800
⇒ ∠D = 1800-1000
⇒ ∠D = 800
Fill in the blanks to make the statements true.
The polygon in which sum of all exterior angles is equal to the sum of interior angles is called ________.
Quadrilateral
Quadrilateral is a polygon whose sum of all exterior angles is equal to the sum of interior angles.
State whether the statements are true (T) or false (F).
All angles of trapezium are equal.
FALSE
In a trapezium all the angles are not equal , rather , Adjacent angles (next to each other) along the sides are supplementary. This means that their measures add up to 180 degrees.
x° + y° = 180°
State whether the statements are true (T) or false (F).
All squares are rectangles.
TRUE
Every square is a rectangle because it is a quadrilateral with all four angles right angles(90°).
State whether the statements are true (T) or false (F).
All kites are squares.
FALSE
All kites are not squares.
A kite is a quadrilateral (four sided shape) where the four sides can be grouped into two pairs of adjacent (next to/connected) sides that are equal length.
So, if all sides are equal, and all angles of the quadrilateral are equal, then only we have a square.
State whether the statements are true (T) or false (F).
All rectangles are parallelograms.
TRUE
A parallelogram is defined as a quadrilateral (4-sided polygon) with both pairs of opposite sides parallel. A rectangle certainly fits that description. In addition, a rectangle must have 4 right angles.
So, you can say that all rectangles are parallelograms
State whether the statements are true (T) or false (F).
All rhombuses are squares.
FALSE
A rhombus is a quadrilateral with all sides equal in length.
A square is a quadrilateral with all sides equal in length and all interior angles right angles.
Thus a rhombus is not a square unless the angles are all right angles.
State whether the statements are true (T) or false (F).
Sum of all the angles of a quadrilateral is 180°.
FALSE
Sum of all the angles of a quadrilateral is 360°.
Because ,the quadrilateral can be divided into 2 triangles and sum of angles of each of the triangles is 180°.
⸫ when we join these 2 triangles to get back the original quadrilateral then the sum of all the angles of the quadrilateral is sum of angles of both the triangles ie. 180°(sum of angles of triangle1) + 180° (sum of angles of triangle2) = 360° (sum of angles of quadrilateral)
State whether the statements are true (T) or false (F).
A quadrilateral has two diagonals.
TRUE
A diagonal is a line segment connecting 2 non consecutive vertices of a polygon , ie. A line segment drawn from one vertex of a quadrilateral to the opposite vertex is called a diagonal of the quadrilateral.
So, as we can see , we can draw only 2 such line segments.
⸫ A quadrilateral can have only two diagonals.
State whether the statements are true (T) or false (F).
Triangle is a polygon whose sum of exterior angles is double the sum of interior angles.
TRUE
We know that,
Sum of Interior angles of Polygon = 180(n-2)
Sum of Exterior angles of Polygon = 360
Here, for triangle , n=3,ie. triangle
So, Sum of Interior angles of triangle = 180(n-2)° = 180(3-2)° = 180°
And ,Sum of Exterior angles of triangle = 360°
⸫ we can say that ,
2 × Sum of Interior angles of triangle = Sum of Interior angles of triangle
2 × 180° = 360°
State whether the statements are true (T) or false (F).
is a polygon.
TRUE
State whether the statements are true (T) or false (F).
A kite is not a convex quadrilateral.
FALSE
A convex polygon is a simple polygon (not self-intersecting) in which no line segment between two points on the boundary ever goes outside the polygon. Equivalently, it is a simple polygon whose interior is a convex set.
⸫ Kite is a convex polygon.
*KITE*
State whether the statements are true (T) or false (F).
The sum of interior angles and the sum of extreme angles taken in an order are equal in case of quadrilaterals only.
TRUE
We know that,
Sum of Interior angles of Polygon = 180(n-2)
Sum of Exterior angles of Polygon = 360
Here, we have n=4
⸫ Sum of Interior angles of Polygon = 180(4-2)=360°
And Sum of Exterior angles of Polygon = 360
⸫ The sum of interior angles and the sum of extreme angles taken in an order are equal in case of quadrilaterals only.
State whether the statements are true (T) or false (F).
If the sum of interior angles is double the sum of exterior angles taken in an order of a polygon. then it is hexagon.
TRUE
In a hexagon number of sides = 6.
∴ Sum of the interior angles of a hexagon = (2n - 4) x 90°
= (2 x 6) - 4) x 90° = 8 x 90° = 720°. -------(1)
Sum of the exterior angles of a hexagon = 360°.
Given that 2 times the sum of the exterior angles of a hexagon ie. 2 x 360°= 720° -----(2)
from (1) and (2) we get
∴ If the sum of interior angles is double the sum of exterior angles taken in an order of a polygon, then it is hexagon.
State whether the statements are true (T) or false (F).
A polygon is regular if all of its sides are equal.
TRUE
A regular polygon is a polygon that is equiangular (all angles are equal in measure) and equilateral (all sides have the same length).
State whether the statements are true (T) or false (F).
Rectangle is a regular quadrilateral.
FALSE
As we know , A regular polygon is a shape whose sides are all the same length, and whose interior angles are all the same measure. A quadrilateral is a polygon with four sides. So a regular quadrilateral is a shape that has four equal sides, with all the interior angles equal., and in a rectangle , only the angles are equal , all the side are not equal , only opposite sides are equal.
⸫ Rectangle is not a regular quadrilateral.
State whether the statements are true (T) or false (F).
If diagonals of a quadrilateral are equal, it must be a rectangle.
FALSE
It is not required that the quadrilateral must be a rectangle , if its diagonals are equal.
In the above picture , we can see that in both the figures , both diagonals are each 5 units long, and the quadrilateral is an isosceles trapezium.
If the diagonals of a quadrilateral are equal the figure could be a rectangle, a square or an isosceles trapezium.
State whether the statements are true (T) or false (F).
If opposite angles of a quadrilateral are equal, it must be parallelogram.
TRUE
Let ABCD be a parallelogram, with A = α and B = β.
We have to Prove that C = α and D = β.
α + β = 180° (co-interior angles, AD || BC),
C = α (co-interior angles, AB || DC)
D = β (co-interior angles, AB || DC).
The interior angles of the triangle are in the ratio 1:2:3, then the ratio of its exterior angles is 3:2:1.
False,
Given:
Ratio of interior angles = 1:2:3
Let the interior angles be x, 2x and 3x
Now, the sum of the interior angles of the triangle are 1800
⇒ x+ 2x + 3x = 1800
⇒ 6x = 1800
⇒ x =
⇒ x = 300
Therefore, the interior angles are: 300, 600 and 900.
Now, the exterior angles will be found by subtracting from 1800 because they form a linear pair.
The exterior angles are: 1500, 1200 and 900.
State whether the statements are true (T) or false (F).
is a concave pentagon.
FALSE
The given figure is not a pentagon because it has 6 sides.
State whether the statements are true (T) or false (F).
Diagonals of a rhombus are equal and perpendicular to each other.
FALSE
Consider rhombus ABCD,
You know that , AB=BC=CD=AD
Now , in ΔAED and ΔCED,
EA = EC (diagonals of a parallelogram bisect each other)
ED= ED (common)
AD=CD
⸫ ΔAED is congruent to ΔCED (SSS)
This gives that AED = CED (CPCT)
But, AED + CED = 180° (linear pair)
So , 2 × AED = 180°
⸫AED = 90°
So , the diagonals of rhombus are only perpendicular to each other.
⸫ the diagonals of rhombus are perpendicular but not equal.
State whether the statements are true (T) or false (F).
Diagonals of a rectangle are equal.
TRUE
Given ABCD is a rectangle
then AC and BD are diagonals
then in ΔABC and ΔBCD,
b is common angle
BC is common side
AB = CD
so by SAS congruency,
Δ ABC is congruent to ΔBCD
so by cpct,
AC = BD
so ,diagonals are equal.
State whether the statements are true (T) or false (F).
Diagonals of a rectangle bisect each other at right angles.
TRUE
In rectangle ABCD, diagonals bisect the angles.
Consider ΔAOD and ΔBOC
AD = BC (ABCD is a rectangle)
∠AOD = ∠BOC (Vertically opposite angles)
∠OAD = ∠OCB = 45° (Diagonals bisect the angles)
ΔAOD ≅ ΔBOC (AAS congruence criterion)
Therefore, OA = OC and OB = OD
Thus the diagonals bisect each other in a rectangle.
State whether the statements are true (T) or false (F).
Every kite is a parallelogram.
FALSE
Kite is a quadrilateral that has 2 adjacent equal sides, that is upper and lower side , whereas in parallelogram , opposite side should be equal.
⸫every kite is not a parallelogram.
State whether the statements are true (T) or false (F).
Every trapezium is a parallelogram.
FALSE
In a parallelogram, both the pairs of sides should be parallel. So , in a trapezium , only one pair of sides is parallel that is it doesn’t fulfill the conditions for parallelogram.
State whether the statements are true (T) or false (F).
Every parallelogram is a rectangle.
FALSE
In a rectangle, all the angles should be equal to 90°. So , all the parallelograms may not have all the angles as 90°.
State whether the statements are true (T) or false (F).
Every trapezium is a rectangle.
FALSE
In a rectangle , all the angles should be equal to 90°. So , all the trapeziums may not have all the angles as 90° , even if they have a pair of parallel sides.
State whether the statements are true (T) or false (F).
Every rectangle is a trapezium.
FALSE
A trapezium is defined to be a quadrilateral that has exactly one pair of parallel sides. Whereas rectangle has 2 pairs of parallel sides. So every rectangle is not a trapezium.
State whether the statements are true (T) or false (F).
Every square is a rhombus.
TRUE
In rhombus, all the sides should be equal and the diagonals should be perpendicular to each other.
This condition is fulfilled by the square.
State whether the statements are true (T) or false (F).
Every square is a parallelogram.
TRUE
In a parallelogram, opposite pairs of sides should be equal and opposite angles should also be equal. These conditions are fulfilled by square.
State whether the statements are true (T) or false (F).
Every square is a trapezium.
FALSE
A trapezium is defined to be a quadrilateral that has exactly one pair of parallel sides. Whereas square has 2 pairs of parallel sides. So every square is not a trapezium.
State whether the statements are true (T) or false (F).
Every rhombus is a trapezium.
FALSE
A trapezium is defined to be a quadrilateral that has exactly one pair of parallel sides. Whereas rhombus has 2 pairs of parallel sides. So every rhombus is not a trapezium.
State whether the statements are true (T) or false (F).
A quadrilateral can be drawn if only measure of four sides are given.
FALSE
To draw a quadrilateral, we need at least 2 angles as well.
State whether the statements are true (T) or false (F).
A quadrilateral can have all four angles as obtuse.
FALSE
As we know that the sum of all the interior angles of the quadrilateral = 360°.
And , if all the 4 angles are obtuse then the above property is violated.
So, A quadrilateral cannot have all four angles as obtuse.
State whether the statements are true (T) or false (F).
A quadrilateral can be drawn if all the four sides and one diagonal is given.
TRUE
Let AB,BC,CD,AD(sides) and AC(diagonal) be given.
Draw ΔABC using SSS construction.
Now, we have to locate the 4th point D. this ‘D’ would be on the side opposite to B with reference to AC.
So, with A as centre draw an arc of radius of length equal to AD.
Now, with C as centre draw an arc of radius of length equal to CD.
The intersection of these 2 arcs is D. Mark D and complete ABCD
State whether the statements are true (T) or false (F).
A quadrilateral can be drawn when all the four angles and one side is given.
FALSE
To construct a quadrilateral, we need at least 3 sides.
State whether the statements are true (T) or false (F).
A quadrilateral can be drawn if all four sides and one angle is known.
FALSE
To construct a quadrilateral, we need at least 2 angles.
State whether the statements are true (T) or false (F).
A quadrilateral can be drawn if three sides and two diagonal diagonals are given.
TRUE
Here, let BC,AD,CD(sides) are given and AC , BD (diagonals)are also given.
Draw ΔACD by using SSS construction.
With D as centre, draw an arc of radius of length equal to BD.
With C as centre, draw an arc of radius of length equal to BC.
The intersection of these 2 arcs is B. Mark B and complete ABCD.
State whether the statements are true (T) or false (F).
If diagonals of a quadrilateral bisect each other. it must be a parallelogram.
FALSE
It is not required that the quadrilateral must be a parallelogram , if its diagonals are equal.
In the above picture , we can see that in both the figures, both diagonals are each 5 units long, and the quadrilateral is an isosceles trapezium.
State whether the statements are true (T) or false (F).
A quadrilateral can be constructed uniquely if three angles and any two sides are given.
TRUE
Let AB, BC(sides) and A,B,C are given.
Draw AB and then B.
From B, draw BC.
At C, draw C.
At M, draw A and mark the point of intersection of these 2 angles as D.
So, we get the required quadrilateral ABCD.
State whether the statements are true (T) or false (F).
A parallelogram can be constructed uniquely if both diagonals and the angle between them is given.
TRUE
Mark a point A and draw a line through A.
From A, draw an arc of radius of length equal to one diagonal to cut the above line at C.
Bisect AC at O.
From A and C, draw arcs of radius more than half the length of AC on both sides, Let they cut at X and Y. XY is the perpendicular bisector of AC. It cuts AC at O.
From O, draw a line at the given angle to AC on both sides.
From O, draw an arc of radius of half the length of another diagonal on both sides of AC to cut the above line at B and D.
Join AB,BC,CD,AD.
State whether the statements are true (T) or false (F).
A rhombus can be constructed uniquely if both diagonals are given.
TRUE
Here only 2 measurements of the rhombus are given ie. The diagonals.
However , since it is a rhombus , we can find more help from its properties.
The diagonals of a rhombus are perpendicular bisectors of one another.
So, first draw AC (any one diagonal) and then construct its perpendicular bisector. Let them meet at E. Cut off half the length of second diagonal on either side of the drawn bisector.
You now get B and D.
Similarly, get A and C, draw the rhombus now.
The diagonal of a rhombus is 8cm and 15 cm. Find its side.
Given, the diagram below:
diagonals of a rhombus, d1 = 8cm
d2 = 15cm
Divide d1 and d2 in two equal halves.
We will get four right angled triangles
Now, the base of each triangle would be, d1/2 = 8/2 = 4cm
And perpendicular would be, d2/2 = 15/2 = 7.5cm
Now, we will find the hypotenuse of each right angled
triangle.
Hence, hypotenuse = side of rhombus
Two adjacent angles of a parallelogram are in the ratio 1:3. Find its angles.
Given, ratio of the adjacent angles of a parallelogram is 1:3
⇒ By the property of parallelogram, the sum of adjacent angles of a parallelogram is 180°.
⇒ Let the adjacent angles are ∠A and ∠B.
∠A = x
∠B = 3x
∠A + ∠B = x + 3x {∠A + ∠B = 180
4x = 180 ̇
x = 45
⇒ ∠A = 45
⇒∠B = 45×3 = 135
Of the four quadrilaterals- square, rectangle, rhombus and trapezium- one is somewhat different from the others because of its design. Find it and gave justification.
According to question, we have four quadrilaterals- square,
Rectangle, rhombus and trapezium.
By the property of parallelogram, a parallelogram is a quadrilateral whose opposite sides are always parallel.
But in case of trapezium, only one pair of opposite sides are parallel. Hence, it is not a parallelogram.
it is clear from the above points that trapezium is different from square, rectangle and rhombus.
In a rectangle ABCD. AB = 25cm and BC = 15cm. In what ration does the bisector of C divides AB?
The figure is given below:
Given, a rectangle ABCD
AB = 25cm
BC = 15cm
Bisector of ∠C divides AB i.e. ∠BCE = 45
⟹ By angle sum property of triangle.
∠BEC = 45
⟹ BC = BE, because sides having equal angles are equal.
BE = 15cm
And AE = AB-BE = 25-15
AE = 10cm
AE:BE = 10:15
AE:BE = 2:3
PQRS is a rectangle. The perpendicular ST from S on PR divides S in the ratio 2:3. Find TPQ.
The figure is given below:
PQRS is a rectangle. The perpendicular ST from S on PR divides angle S in the ratio 2:3.
∠PSR = 90
⟹ It is given that, the perpendicular ST from S on PR divides angle S in the ratio 2:3.
⟹ divide the 90° angle into the ratio 2:3.
2x + 3x = 90
5x = 90
x = 18
⟹ therefore, 2x = 2×18 = 36 and 3x = 3×18 = 54
now, ∠PST = 36 and
∠TSR = 54 = ∠TSQ + ∠QSR
∠PST = 36
∠TSR = 54 = ∠TPS
Hence, ∠TPQ = ∠SPQ-∠TPS = 90-54 = 36
A photo frame is in the shape of quadrilateral. With one diagonal longer than the other. Is it a rectangle? Why or why not?
A photo frame is in the shape of quadrilateral with one diagonal longer than the other. So, That quadrilateral-shaped frame is not in shape of rectangle. As we know rectangle have equal diagonals.
The adjacent angles of a parallelogram are (2x -4)° and (3x - 1) °. Find the measures of all angles of the parallelogram.
Given, adjacent angles are (2x-4) and (3x-1)
⟹ (2x-4) + (3x-1) = 180
⟹ (5x-5) = 180
⟹ 5(x-1) = 180
⟹ x-1 = 36
⟹ x = 37
⟹ First angle = 2x-4 = (2×37)-4 = 70
⟹ Second angle = 3x-1 = (3×37)-1 = 110
The point of intersection of diagonals of a quadrilateral divides one diagonal in the ration 1:2. Can it be a parallelogram? Why or why not?
No, it cannot be a parallelogram because the diagonal of a parallelogram are always bisect each other i.e. in the ratio 1:1.
The ration between exterior angle and interior angle of a regular polygon is 1:5. Find the number of sides of the polygon.
Given, the ratio between exterior angle and interior angle is
1:2.
Let, exterior angle = x
And, interior angle = 5x
Sum of exterior and interior angle is equal to 180.
Hence, x + 5x = 180
6x = 180
x = 30
⟹Total measure of all the exterior angle = 360
⟹Measure of each exterior angle = 30
Therefore, the number of all exterior angles
Hence, the polygon has 12 sides.
Two sticks each of length 5cm are crossing each other such that they bisect each other. What shape is formed by joining their end points? Give reason.
Given, two sticks each of length 5cm i.e. equal in length.
If the diagonal of a quadrilateral are equal and bisects each
Other then the quadrilateral is a rectangle. Hence, the shape
Formed by joining given two sticks will be a rectangle.
Two sticks each of length 7cm are crossing each other such that they bisect each other at right angle. What shape is formed by joining their end points? Give reasons.
Given, two sticks each of length 7cm i.e. equal in length.
If the diagonal of a quadrilateral are equal and bisects each
Other at right angle then the quadrilateral is a rhombus. Hence, the shape formed by joining given two sticks will be a rhombus.
A playground in the town is in the form of a kite. The perimeter is 106 metres. If one of its sides is 23 metres. What are the lengths of other three sides?
The kite has four sides. There are exactly two distinct consecutive pairs of sides of equal length.
Let two different length be A and B.
Then the perimeter = 2A + 2B _______(i)
Given, perimeter = 106m
And one side i.e = 23m
According to Eq.(i), (2 × 23) + 2B = 106
2B = 60
B = 30
Hence, all sides are 23, 23, 30, 30.
In rectangle READ. Find ∠EAR, ∠ RAD and ∠ROD.
Given, ∠ROE = 60
According to given figure, ∠AOE = 120, ∠AOD = 60 and ∠ROD = 120.
⟹In triangle AOE, consider ∠EAR = ∠DEA = x
∠AOE + ∠EAR + ∠DEA = 180
x + x + 120 = 180
2x + 120 = 180
2x = 60
x = 30, i.e. ∠EAR = 30
⟹In triangle AOD, consider ∠RAD, = ∠EDA = y
∠RAD + ∠EAR + ∠AOD = 180
y + y + 60 = 180
2y = 120
y = 60, i.e.∠RAD = 60.
In rectangle PAIR. Find ∠ARI, ∠RMI and ∠PMA.
Given, ∠RAI = 35
⟹In ∆ARI,
∠A + ∠R + ∠I = 180
35 + ∠ARI + 90 = 180
∠ARI = 55
⟹In ∆RMI,
∠R + ∠M + ∠I = 180
∠ARI + ∠RMI + ∠ARI = 180 {∠ARI = ∠MIR = 55}
(2×55) + ∠RMI = 180
∠RMI = 70
And, ∠PMA = 180-∠RMI
∠PMA = 180-70
∠PMA = 110
In parallelogram ABCD, find∠ B, ∠C and ∠D.
Given, ∠A = 80
⟹The sum of the adjacent angles of a parallelogram is 180
Hence, ∠A + ∠B = 180
∠B = 180-80
∠B = 100
⟹The opposite angles of a parallelogram are equal.
Hence, ∠C = ∠A = 80
And, ∠D = ∠B = 100
In parallelogram PQRS. O is the mid-point of SQ. Find ∠S, ∠R. PQ, Qr and diagonal PR.
Given:
∠RQY = 60°
∵ ∠RQY and ∠RQP form a linear pair
⇒ ∠RQP = 180° - ∠RQY = 120°
∴ ∠RQP =120°
Now, in a parallelogram, the opposite sides are equal,
⇒ ∠RQP = ∠S = 120°
Similarly, ∠P = ∠R
Now, from the angle sum property of a quadrilateral,
∠P + ∠R + ∠Q + ∠S = 360°
⇒ ∠P + ∠R + 120° + 120° = 360°
⇒ 2∠P = 120°
⇒ ∠P = 60°
⇒ ∠R = 60°
Now,
Opposite sides of the parallelogram are equal.
⇒ SR = PQ = 15 cm
Also, PS = QR = 11 cm
And, the diagonals of the parallelogram bisect each other.
Hence, PR = 2×PQ = 2×6 = 12 cm.
In rhombus BEAM. Find AME and AEM.
In the rhombus,
∠BAM = 700
Also, we know that the diagonals of a rhombus bisect at 900
∴ ∠AOM = 90
Now, in ΔAOM,
∠AOM + ∠OMA + ∠MOA = 1800
⇒ 90 + ∠OMA + 70 = 1800
⇒ ∠AME = ∠OMA = 200
Also,
The sides in the rhombus are equal.
Ans, we know, equal sides make equal angles.
⇒ ∠AEM = 200
In parallelogram FIST. Find SFT, OST and STO.
Given, ∠TOF,∠TIS and ∠TIF
⟹In ∆TOF,
∠T + ∠O + ∠F = 180
25 + 110 + ∠SFT = 180
∠SFT = 180-135
∠SFT = 45
⟹In ∆TOS,
∠T + ∠O + ∠S = 180
35 + (180-110) + ∠OST = 180
35 + 70 + ∠OST = 180
∠OST = 180-105
∠OST = 75
∠STO = ∠T(in triangle SOT) = 35
In the given parallelogram YOUR, ∠RUO = 120° ad OY is extended to point S such that ∠SRY = 50°. Find ∠YSR.
Given, ∠RUO = 120 and ∠SRY = 50
⟹The opposite angles of a parallelogram are equal.
Hence, ∠RYO = 120
⟹In ∆YSR,
∠Y + ∠R + S = 180
(180-120) + 50 + ∠YSR = 180
110 + ∠YSR = 180
∠YSR = 70
In kite WEAR, ∠WEA = 70° and ∠ARW = 80°. Find the remaining two angles.
In ∆ARW,
∠R + ∠A + ∠W = 180
⟹Let ∠A = ∠W = x
80 + 2x = 180
2x = 180-80
x = 50
⟹In ∆WEA,
∠W + ∠E + ∠A = 180
⟹Let ∠W = ∠A = y
2y + 70 = 180
2y + 180-70
y = 55
⟹Hence, ∠RWE = ∠RAE = (x + y)
= (50 + 55)
= 105
A rectangular MORE, is shown below:
Answer the following questions by giving appropriate reason.
(i) Is RE = OM? (ii) Is MYO = RXE?
(iii) Is MOY = REX? (iv) Is ∆MYO = ∆RXE?
(v) Is MY = RX?
(i) Yes,
∵ MORE is a rectangle.
And, the opposite sides of the rectangle are equal.
∴ RE = OM
(ii) Yes,
In the MORE rectangle,
MY and RX are perpendicular to OE
⇒ ∠RXO = ∠RXE = ∠MYE = ∠MYO = 900
∴ ∠MYO = ∠RXE
(iii) Yes,
∵ in rectangle MORE, RE||OM and EO is transveral.
From the property of alternate interior angles being equal.
∴ ∠MOE = ∠OER
⇒ ∠MOY = ∠REX
(iv) Yes,
In, ΔMYO and Δ RXE,
MO = RE
∠MOY = ∠REX
∠MYO = ∠RXE
∴ ΔMYO ≅ ΔRXE
(v) Yes.
Corresponding parts of congruent triangles are equal.
In parallelogram LOST, SN Ol and SM LT. Find STM, SON and NSM.
⟹In ∆STM,
∠S + ∠T + ∠M = 180
40 + ∠STM + 90 = 180
∠STM = 180-130 = 50
∠STM = ∠SON (these are opposite angles).
∠SON = 50
∠SON and ∠OST are adjacent angles.
⟹Hence, ∠SON + ∠NSO + ∠NSM + ∠MST = 180
50 + (180-(90 + 50)) + ∠NSM + 40 = 180
∠NSM = 140-90
∠NSM = 50
In trapezium HARE. EP and RP are bisectors of E and R respectively. find ∠HAR and ∠EHA.
Adjacent angles along a side of a trapezium are supplementary.
Hence, ∠R + ∠A = 180 ________(i)
Similarly, ∠E + ∠H = 180 ________(ii)
According to given data in question,
The complete ∠R = 2×30 = 60
And ∠E = 2×25 = 50
Because, EP and RP are bisectors of E and R respectively.
By Eq (i) and (ii),
∠A = 180-60 = 120
∠H = 180-50 = 130
In parallelogram MODE, the bisector of ∠M and O meet at Q. Find the measure of ∠MQO.
Let MODE be the parallelogram and Q be the point of intersection of the bisector of ∠M and ∠O
The figure is attached below:
Now, in a parallelogram, the adjacent angles are supplementary.
∴ ∠EMO + ∠DOM = 180°
⇒ 1/2 (∠EMO + ∠DOM) = 1/2 180°
⇒ 1/2∠EMO + 1/2∠DOM = 1/2 180°
∠QMO + ∠QOM = 90°
Now, in ΔMOQ,
∠QMO + ∠QOM + ∠MQO = 1800
⇒ 900 + ∠MQO = 1800
⇒ ∠MQO = 900
A playground is in the form of a rectangular ATEF, two players are standing at the points of F and B where EF = EB. Find the values of x and y.
EBF formed a isosceles triangle.
⟹Hence, ∠EBF = ∠EFB = 45
⟹According to question,
∠EBF + ∠x = 180
∠x = 180-45 = 135
⟹And ∠EFB + y = 90
∠y = 90-45 = 45
In the following figure of a ship. ABDH and CEFG are two parallelograms. Find the value of x.
⟹In llgm ABDH,
∠D = ∠BAH = 180-130(adjacent angles)
⟹In llgm CEFG,
∠C = ∠GCE = ∠GFE = 30(opposite angles)
⟹Hence, in ∆CDX,
∠C + ∠D + ∠x = 180
30 + 130 + ∠x = 180
∠x = 180-160 = 20
A rangoli has been drawn on a floor of house. ABCD and PQRS both are in the shape of a rhombus ABCD.
In Rhombus ABCD,
AO = OP + PA = 2+2 = 4 units.
And, OB = OQ + QB = 2 + 1 = 2 units.
Now,
We know that the diagonals of the rhombus bisect at 900
∴ in ΔOAB,
AB2 = OA2 + OB2
⇒ AB2 = 42 + 32
⇒ AB = √25
⇒ AB = 5 units.
Now, AB is also the diameter of the semi-circle.
∴ radius of the circle will be 2.5 units.
ABCDE is a regular pentagon. The bisector of angle A meets the side CD at M. Find AMC
The figure is attached below:
I have circumscribed the regular Pentagon with a circle. Since, the 360° of the circle is divided equally by the pentagon to five parts.
⇒ ∠COD =
Using the properties of circle,
∠CAD = 1/2 ∠COD
⇒ ∠CAD = 1/2 720
∠CAD = 360
Now, in ∆ACD.
36° + ∠ACD + ∠ADC = 180°
Since, ∆ACD is an isosceles ∆,
36° + 2×∠ACD = 180°
∠ACD = 72°
Now, in ∆AMC.
∠MAC = 1/2 ∠CAD = 18°
Now,
∠MAC + ∠AMC + ∠ACM = 180°
18° + ∠AMC + 72° = 180°
∠AMC = 90°
Quadrilateral EFGH is a rectangular in which J is the point of intersection of the diagonals. Find the value of x if JF = 8x + 4 and EG = 24x-8.
By the property of rectangle, the length of both the diagonals are equal.
Hence, FH = EG
2(JF) = EG
2(8x + 4) = (24x-8)
16x + 8 = 24x-8
8x = 16
x = 2