what is $m\\angle 1$? \n$m\\angle 1 = \\square ^\\circ$
what is $m\\angle 1$? \n$m\\angle 1 = \\square ^\\circ$
Answer
Explanation:
Step1: Find adjacent interior angle
The 138° angle is an exterior angle, so its adjacent interior angle is $180^\circ - 138^\circ = 42^\circ$.
Step2: Calculate $\boldsymbol{m\angle1}$
Use triangle angle sum ($180^\circ$). Subtract the two known interior angles. $m\angle1 = 180^\circ - 99^\circ - 42^\circ$
Answer:
$41^\circ$