Question

The measure of an angle is 78 degrees. what is the measure of its supplementary angle?

Answer 1

18*

Explanation:

When two angles add up to 90°, we say they "Complement" each other.

Complementary comes from Latin completum meaning "completed" ...

because the right angle is thought of as being a complete angle.

Spelling: be careful, it is not "Complimentary Angle" (with an "i") ...

that would be an angle you get for free!

Answer 2

I hope this helps :D

An angle of 78° is a supplement of another angle. We know that the sum of the supplementary angles is 180° and the sum of complementary angles is 90°. Let's take another angle to be x. Hence, the measure of another angle is 102°.