Illustrating Exterior Angle Inequality Theorem

1. What do you call the angle formed between one side of a triangle and its adjacent extended side?

• Interior Angle

• Exterior Angle

• Remote Interior Angle

• Supplementary Angle

2. What do you call an angle of a triangle that is not adjacent to a specified exterior angle?

• Interior Angle

• Exterior Angle

• Remote Interior Angle

• Supplementary Angle

3. The measure of an exterior angle of a triangle is equal to the sum of the measures of its remote interior angles.

• True

• False

• Maybe

• Cannot be determined

4. The measure of an exterior angle of a triangle is always _________.

• equal to its adjacent interior angle

• less than its adjacent interior angle

• less than either remote interior angle

• greater than either remote interior angle

5. If ∠1 and ∠2 are the remote interior angles of the exterior angle ∠3, what conclusion can you draw based on the Exterior Angle Inequality Theorem?

• ∠2 < ∠3

• ∠3 > ∠1

• ∠3 = ∠1 + ∠2

• All of the above

6. ∠2 is adjacent to the exterior angle ∠3. Using the Exterior Angle Inequality Theorem, can we conclude that ∠3 > ∠2?

• Yes

• No

• Maybe

• Cannot be determined

Bonus

8. Name the exterior angle/s of the triangles shown in the figure.

• ∠1, ∠2

• ∠4, ∠5

• ∠1, ∠2,∠3

• ∠4, ∠5,∠6

9. Which of the following is the exterior angle of ∆EAR?

• ∠1

• ∠2

• ∠3

• All of the above

10. In the figure, which of the following statements is true?

• m∠DEB > m∠DCE

• m∠DEB < m∠DCE

• m∠DEB < m∠CDE

• All of the above