Question

what is $m\angle1$?
$m\angle1=\square^\circ$

Explanation:

Step1: Find adjacent interior angle

The 150° angle is supplementary to its adjacent interior angle of the triangle.
$180^\circ - 150^\circ = 30^\circ$

Step2: Find adjacent interior angle

The 118° angle is an interior angle of the triangle, no adjustment needed.

Step3: Calculate $m\angle1$

Use triangle angle sum theorem (sum = 180°).
$m\angle1 = 180^\circ - 30^\circ - 118^\circ$

Answer:

$42$