Answer:
angle 1 = 120 degree
Step-by-step explanation:
75 degree + 45 degree = angle 1 (sum of two opposite interior angles is equal to the exterior angle formed)
120 degree = angle 1
120
75 + 45 = 120
The triangle adds up to 180.
180 - 120 = 60
Therefore the inside of the triangle is 75, 45, and now 60 which all adds up to 180.
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Now to find Angle 1.
180 - 60 = 120
With Angle 1 being 120
