Question

look at this diagram: if $overleftrightarrow{oq}$ and $overleftrightarrow{rt}$ are parallel lines and $mangle{opn}=139^{circ}$, what is $mangle{ops}$?

Explanation:

Step1: Identify angle - relationship

$\angle{OPN}$ and $\angle{OPS}$ are supplementary angles.

Step2: Use the supplementary - angle formula

Supplementary angles add up to 180°. Let $m\angle{OPS}=x$. Then $m\angle{OPN}+x = 180^{\circ}$.
Given $m\angle{OPN}=139^{\circ}$, we have $x=180 - 139$.
$x = 41^{\circ}$

Answer:

$41$