### Home > ACC7 > Chapter 9 Unit 6 > Lesson CC2: 9.1.1 > Problem9-21

9-21.

Review the definitions of complementary, supplementary, and vertical angles. Use the information to answer the following questions.

1. Two angles are complementary. If one measures $65º$, what is the measure of the other angle?

Two angles whose measurements add up to $90º$ are called complementary.

2. Two angles are supplementary. If one measures $125º$, what is the measure of the other angle?

Two angles whose measurements add up to $180º$ are called supplementary.

3. Two angles are vertical. If one measures $63º$, what is the measure of the other angle?

Vertical angles have equal measures.