Answer: x = 45
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Work Shown:
The smaller pieces x, 65 and (2x-20) combine to form a straight line. So the smaller angles add to 180 degrees
x+65+(2x-20) = 180
3x+45 = 180
3x = 180-45
3x = 135
x = 135/3
x = 45
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Extra info:
Note how if x = 45, then,
2x-20 = 2*45-20 = 90-20 = 70
So the three angles are:
As a check, the angles should add to 180
45+65+70 = 110+70 = 180
The answer is confirmed.
