Question

An angle is equal to one-third of its supplement. Find its measure. [2 MARKS]

Answer 1

Concept: 1 Mark
Application: 1 Mark

Let the measure of the required angle be x degrees. Then,

It's supplement $={180}^{\circ }-x$

It is given that

$x=\frac{1}{3}({180}^{\circ }-x)$

$3x={180}^{\circ }-x$

$4x={180}^{\circ }$

$x={45}^{\circ }$

Thus, the measure of the given angle is ${45}^{\circ }$.