Question

for the figure shown, find m∠1. (the figure is not drawn to scale.) m∠1 = ​°

Explanation:

Step1: Recall angle - sum property of a triangle

The sum of the interior angles of a triangle is $180^{\circ}$.

Step2: Set up an equation

Let the third angle of the triangle be $\angle1$. We know two angles are $118^{\circ}$ and $57^{\circ}$. So, $m\angle1+118^{\circ}+57^{\circ}=180^{\circ}$.

Step3: Solve for $m\angle1$

$m\angle1=180^{\circ}-(118^{\circ} + 57^{\circ})=180^{\circ}-175^{\circ}=5^{\circ}$.

Answer:

$5$