Question

2. Lines r and s are parallel and lines I and m are perpendicular. Find the measure of angle 5, if m

Answer 1

Line l and m intersect at a right angle.

$m\angle2=120^{\circ}$

Therefore,

$m\angle5+m\angle3=90^{\circ}$$\begin{gathered} m\angle3=180-120=60^{\circ}(supplementary\text{ angle)} \\ 60^{\circ}+m\angle5=90^{\circ} \\ m\angle5=90^{\circ}-60^{\circ} \\ m\angle5=30^{\circ} \end{gathered}$