<PRE><B>Question 211072</B>
Let the angle be A, then:
90-A = (1/5)(180-A)-10 Simplify and solve for A.
90-A = 36-(1/5)A-10
90-A = 26-(1/5)A Add A to both sides.
90 = 26+(4/5)A Subtract 26 from both sides.
64 = (4/5)A Multiply both sides by 5/4
80 = A
The angle is 80 degrees.
Check:
90-80 = (1/5)(180-80)-10
10 = (1/5)(100)-10
10 = 20-10
10 = 10
Good night and sleep well!
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