Question

look at this diagram: if $overleftrightarrow{hj}$ and $overleftrightarrow{km}$ are parallel lines and $mangle jig = 60^{circ}$, what is $mangle jil$?

Explanation:

Step1: Recall angle - addition property

$\angle JIG+\angle JIL = 180^{\circ}$ (linear - pair of angles).

Step2: Solve for $\angle JIL$

Given $\angle JIG = 60^{\circ}$, then $\angle JIL=180^{\circ}-\angle JIG$. Substitute $\angle JIG = 60^{\circ}$ into the equation: $\angle JIL = 180 - 60=120^{\circ}$.

Answer:

$120$