Question

what is m∠1? m∠1 = °

Explanation:

Step1: Recall exterior - angle property

The exterior - angle of a triangle is equal to the sum of the two non - adjacent interior angles.
Let the exterior angle be $77^{\circ}$, and the two non - adjacent interior angles be $33^{\circ}$ and $\angle1$. So, $77^{\circ}=33^{\circ}+m\angle1$.

Step2: Solve for $m\angle1$

Subtract $33^{\circ}$ from both sides of the equation: $m\angle1 = 77^{\circ}-33^{\circ}$.
$m\angle1=44^{\circ}$

Answer:

$44$