### Home > MC1 > Chapter 8 > Lesson 8.2.4 > Problem8-66

8-66.

Two angles whose measurements give a sum of $180°$ are called supplementary angles. Two angles whose measurements give a sum of $90°$ are called complementary angles. Use the definitions of complementary and supplementary angles to determine the value of each variable in the following figures. Do not use a protractor.

1. $37°$ and $a$ are complementary angles. Their sum is $90°$.

$90° − 37° = 53°$

1. $95°$ and $b$ are supplementary angles. Their sum is $180°$.