Triangles Quiz

In a triangle, one of the exterior angle is 125°. If one of the corresponding interior opposite angle is 80°. Find the other interior opposite angle.

1. 45°
2. 50°
3. 55°
4. 60°

Answer: (a) 45°

The measure of one angle of a triangle is equal to the sum of measures of remaining two angles. Determine the type of triangle.

1. Equilateral triangle
2. Obtuse-angled triangle
3. Right-angled triangle
4. Acute-angled triangle

Answer: (c) Right-angled triangle

Find the value of x in the following figure:

1. 70°
2. 135°
3. 115°
4. 60°

Answer: (b) 135°

Determine the largest angle in a triangle PQR, where ∠P + ∠R = 105° and ∠Q + ∠R = 145°.

1. ∠R = 70°
2. ∠Q = 75°
3. ∠P = 35°
4. ∠R = 80°

Answer: (b) ∠Q = 75°

The length of one side of a rhombus is 10 cm; the length of one of its diagonals is 12 cm. Determine the length of the other diagonal.

1. 6 cm
2. 16 cm
3. 10 cm
4. 8 cm

Answer: (b) 16 cm

In the given figure, DEFB is a trapezium formed by a rectangle AEDB and a triangle AFE. ∠BED = 25°, ∠AFE = 35°, ED = 25 cm, FE = 13 cm and AF = 5 cm. Determine the value of ∠FEB and the length of side BD.

1. 120° , 12 cm
2. 65°, 12 cm
3. 120°, 5 cm
4. 100°, 10 cm

Answer: (a) 120° , 12 cm

The triangles PQR and MNO are congruent by the SAS congruence rule. Find the value of x, y and z.

1. 10, 6, 24
2. 2, 6, 28
3. 3, 4, 10
4. 4, 3, 10

Answer: (d) 4, 3, 10

A ladder reaches a window that is at a height of 15 m from the ground when the foot of the ladder is placed at a distance of 20 m from the base of the room. Can the same ladder be used to reach a wall of height 16 cm if it is placed at a distance of 21 m from the foot of the wall?

1. Yes
2. No
3. Yes, when the ladder is placed at a distance of 19 m from the foot of the wall
4. None of these

Answer: (b) No

Read the passage carefully and answer the following question. Rachel and Peter draw a triangle ABD. They take a point C on the side BD and join it to the vertex A and observe that AC is equal to CD. After this, John extends the side BD of triangle ABD to E and joins point E to point F on the side AD. They measure that ∠ABC = 25° and ∠ACD = 50° and name some unknown angles as x, y, z and w as shown in the figure. What is the measure of ∠y?

1. 75°
2. 90°
3. 25°
4. 65°

Answer: (c) 25°

Read the passage carefully and answer the following question. Rachel and Peter draw a triangle ABD. They take a point C on the side BD and join it to the vertex A and observe that AC is equal to CD. After this, John extends the side BD of triangle ABD to E and joins point E to point F on the side AD. They measure that ∠ABC = 25° and ∠ACD = 50° and name some unknown angles as x, y, z and w as shown in the figure. Rachel finds a relation between ∠x and ∠y. What is that relation?

1. ∠x = 2∠y
2. ∠y = ∠x + 90°
3. ∠x + ∠y = 65°
4. ∠x - ∠y = 90°

Answer: (d) ∠x - ∠y = 90°