Chapter 12.1, Problem 4E

To determine

Whether a given pair of angles are complementary, supplementary or neither.

Answer to Problem 4E

The pair of angles measuring $m\angle 3={108}^o$ and $m\angle 4={72}^o$ are supplementary to each other.

Explanation of Solution

Given Information: The measures of the two angles are $m\angle 3={108}^o$ and $m\angle 4={72}^o$

Concept Used: If the sum of the measures of two angles is ${90}^o$ then the angles are called complementary angles and if the sum is ${180}^o$ then the angles are called supplementary angles.

The sum of the measures of the two angles is $m\angle 3+m\angle 4=108+72={180}^o$ .

Therefore, the given two angles are a supplementary angle pair. $$