# Supplementary Angles

When the sum of the measures of two angles is 180°, the angles are called **supplementary angles**.

For examples the following pairs are complementary:

(a) 30° and 150°

(b) 145° and 35°

(c) 100° and 80°

When two angles are complementary, each angle is said to be the **supplement** of the other angle. The '**100° angle**' is supplement of the '**80° angle**'.