Angles & Triangles Quiz

1. What is the sum of angles in a triangle?

1. 180°
2. 270°
3. 360°
4. 90°

2. What type of angle is exactly 90°?

1. Acute
2. Obtuse
3. Reflex
4. Right

3. A triangle has angles of 60°, 60°, and 60°. What type is it?

1. Equilateral
2. Isosceles
3. Right-angled
4. Scalene

4. What is a reflex angle?

1. Between 90° and 180°
2. Exactly 180°
3. Greater than 180°
4. Less than 90°

5. In a right-angled triangle, the side opposite the right angle is called?

1. Adjacent
2. Base
3. Hypotenuse
4. Opposite

6. Two angles in a triangle are 70° and 45°. What is the third angle?

1. 55°
2. 60°
3. 65°
4. 75°

7. What are angles on a straight line called, and what do they sum to?

1. Complementary, 90°
2. Supplementary, 180°
3. Supplementary, 90°
4. Vertically opposite, 360°

8. A triangle has sides of different lengths. What is it called?

1. Acute
2. Equilateral
3. Isosceles
4. Scalene

9. What do the angles around a point sum to?

1. 180°
2. 270°
3. 360°
4. 90°

10. What are vertically opposite angles?

1. Angles in the same triangle
2. Angles that add to 180°
3. Angles that add to 90°
4. Equal angles formed when two lines cross

11. A triangle has two equal sides. What is it called?

1. Equilateral
2. Isosceles
3. Right-angled
4. Scalene

12. What is the Pythagorean theorem?

1. 2a + 2b = c²
2. a + b = c
3. a² + b² = c²
4. a² − b² = c

13. A right-angled triangle has legs of 3 and 4. What is the hypotenuse?

1. 5
2. 6
3. 7
4. 9

14. What angle is formed by alternate angles when a line crosses two parallel lines?

1. They are complementary
2. They are equal
3. They are right angles
4. They are supplementary

15. What is an obtuse triangle?

1. A triangle with all angles less than 90°
2. A triangle with equal sides
3. A triangle with one angle greater than 90°
4. A triangle with one right angle

16. Co-interior angles (also called same-side interior angles) between parallel lines sum to?

1. 180°
2. 270°
3. 360°
4. 90°

17. What is the area of a triangle with base 10 cm and height 6 cm?

1. 120 cm²
2. 16 cm²
3. 30 cm²
4. 60 cm²

18. A right-angled triangle has legs of 5 and 12. What is the hypotenuse?

1. 13
2. 14
3. 15
4. 17

19. The exterior angle of a triangle equals?

1. 180° minus the adjacent angle
2. The average of all interior angles
3. The largest interior angle
4. The sum of the two non-adjacent interior angles

20. What do corresponding angles equal when a transversal crosses parallel lines?

1. They add to 180°
2. They add to 90°
3. They are equal
4. They are supplementary