Question

1. find m∠1. 123° 57° 83° 132°

Explanation:

Step1: Recall exterior - angle property

The exterior angle of a triangle is equal to the sum of the two non - adjacent interior angles.

Step2: Identify non - adjacent interior angles

The two non - adjacent interior angles to angle 1 are 60° and 63°.

Step3: Calculate angle 1

Angle 1=60° + 63° = 123°.

Answer:

123°