Question

If < A and < B are complementary, and < A = 36 °, what is the measure of < B?

Answer 1

Two angles are complementary, if the sum of two angles is equal to 90 degrees. So,

$\angle A+\angle B=90$

Substitute 36 for angle A in the equation to determine the measure of angle B.

$\begin{gathered} 36+\angle B=90 \\ \angle B=90-36 \\ =54 \end{gathered}$

So measure of angle B is 54 degrees.