Question

If angle A and angle B are supplementary and angle A = 4x - 8 and angle B = 2x +2, what is the value of x?

Answer 1

Step 1

Given; If angle A and angle B are supplementary and angle A = 4x - 8 and angle B = 2x +2, what is the value of x?

Step 2

Two angles are called supplementary when their measures add up to 180 degrees.

Thus;

$\begin{gathered} m\angle A\text{ + m}\angle B=180^o \\ 4x-8+(2x+2)=180^o \end{gathered}$$\begin{gathered} 4x+2x+2-8=180^o \\ 6x-6=180 \\ 6x=180+6 \\ 6x=186 \\ \frac{6x}{6}=\frac{186}{6} \\ x=31 \end{gathered}$

Answer;

$x=31$