Question

in the figure, the measure of angle abd is 135°. which equation can be used to find the measure of angle abc? (a) 135 - m = 50 (b) 135 + m = 50 (c) 135 + m = 50 (d) 135 = m - 50

Explanation:

Step1: Identify angle - relationship

We know that $\angle ABD=\angle ABC + \angle CBD$. Given $\angle ABD = 135^{\circ}$ and $\angle CBD=50^{\circ}$, let $m$ be the measure of $\angle ABC$.
So, $135=m + 50$, which can be rewritten as $135 - m=50$.

Answer:

A. $135 - m = 50$