Question

find the measure of the missing angles.

Explanation:

Step1: Use vertical - angle property

Vertical angles are equal. Angle $b$ and the given $80^{\circ}$ angle are vertical angles. So $b = 80^{\circ}$.

Step2: Use linear - pair property

The sum of angles in a linear pair is $180^{\circ}$. Angle $c$ and the $80^{\circ}$ angle form a linear pair. So $c=180 - 80=100^{\circ}$.

Answer:

$b = 80^{\circ}$, $c = 100^{\circ}$