Question

An angle is equal to one-third of its supplement. Find its measure.

Answer 1

Let angle be $\frac{x}{3}$, then its supplementary will be x

$x+\frac{x}{3}=\frac{4}{3}x=180$

$x={135}^o$

$\frac{135}{3}={45}^o$ is measure of angle.