Question

look at this diagram: if $overleftrightarrow{df}$ and $overleftrightarrow{gi}$ are parallel lines and $mangle fec = 53^{circ}$, what is $mangle deh$?

Explanation:

Step1: Identify vertical - angle relationship

$\angle FEC$ and $\angle DEH$ are vertical angles.

Step2: Recall vertical - angle property

Vertical angles are congruent, so $m\angle DEH=m\angle FEC$.

Answer:

$53$