Question

look at this diagram: if $overleftrightarrow{hj}$ and $overleftrightarrow{km}$ are parallel lines and $mangle kli = 51^{circ}$, what is $mangle mli$?

Explanation:

Step1: Identify angle - relationship

$\angle KLI$ and $\angle MLI$ are supplementary angles (linear - pair).

Step2: Use supplementary - angle property

Supplementary angles add up to $180^{\circ}$. Let $m\angle KLI = 51^{\circ}$ and $m\angle MLI=x$. Then $x + 51^{\circ}=180^{\circ}$.

Step3: Solve for $x$

$x=180^{\circ}-51^{\circ}$.
$x = 129^{\circ}$

Answer:

$129$