Interior Angles of a Polygon

Q.

If one angle of a triangle is equal to the sum of the other two angles which are equal, then the triangle is a/an _________ .

1. Acute angled triangle

2. Obtuse angled triangle

3. Right angled triangle

4. Equilateral triangle

Q.

Which polygon has an interior angle sum of $1080°$?

Q. One of the angles of a triangle is ${74}^{\circ }$ and the other two angles are equal, then the measure of each of the equal angles is:

1. ${58}^{\circ }$
2. ${100}^{\circ }$
3. ${53}^{\circ }$
4. ${116}^{\circ }$

Q. If three angles of a triangle are in the ratio 2:3:4, then the measure of the three angles are:

1. ${20}^{\circ },{60}^{\circ },{100}^{\circ }$
2. ${40}^{\circ },{60}^{\circ },{80}^{\circ }$
3. ${40}^{\circ },{50}^{\circ },{90}^{\circ }$
4. ${50}^{\circ },{60}^{\circ },{70}^{\circ }$

Q. Two angles of a triangle are in the ratio $(\frac{2}{3}:\frac{3}{2})$ and the third angle is ${50}^{\circ }$. The two angles are:

1. ${30}^{\circ },{95}^{\circ }$
2. ${45}^{\circ },{85}^{\circ }$
3. ${30}^{\circ },{100}^{\circ }$
4. ${40}^{\circ },{90}^{\circ }$

Q.

The sum of the interior angles of an octagon is equal to ___

1. 8 right angles

2. 12 right angles

3. 9 right angles

4. 10 right angles

Q.

The sum of all the interior angles of a regular octagon is:

1. ${360}^{\circ }$

2. ${1080}^{\circ }$

3. ${1440}^{\circ }$

4. ${1260}^{\circ }$

Q.

Find the value of X in the figure below:

1. 60${}^{\circ }$

2. 70${}^{\circ }$

3. 80${}^{\circ }$

4. 90${}^{\circ }$

Q. In $\Delta ABC$, $\angle B={105}^{\circ }$, $\angle C={50}^{\circ }$. Find $\angle A$.
(2 marks)

Q.

Which of the following regular polygons has sum of all the interior angles as 720°?

1. Regular hexagon

2. Pentagon

3. Equilateral triangle

4. Rhombus

Q. What is the sum of all the interior angles of a pentagon?

1. 720 degrees
2. 540 degrees
3. 360 degrees
4. It depends on the type of pentagon.

Q.

Sum of interior angles of a polygon doesn't depend on number of sides.

1. True

2. False