Answer: 125 degrees
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Explanation:
Use the remote interior angle theorem
The two interior angles 65 and x+15 add to the exterior angle 3x-10
These interior angles are not adjacent to the exterior angle
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(65) + (x+15) = 3x-10
x+80 = 3x-10
80+10 = 3x-x
2x = 90
x = 90/2
x = 45
This leads to
3x-10 = 3*45-10 = 135-10 = 125
The exterior angle is 125 degrees
