Question

angles a and b are supplementary. if a = 112°, what is the value of b? 78° 68° 92° 88°

Explanation:

Step1: Recall supplementary - angle definition

Supplementary angles sum to $180^{\circ}$, so $A + B=180^{\circ}$.

Step2: Solve for angle B

$B = 180^{\circ}-A$. Substitute $A = 112^{\circ}$, then $B=180^{\circ}- 112^{\circ}=68^{\circ}$.

Answer:

B. $68^{\circ}$