SOLUTION: In a certain triangle, angle A is seven times as large as angle B. Angle C is 30° more than angle A. How large is angle A?

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Question 1070835: In a certain triangle, angle A is seven times as large as angle B. Angle C is 30° more than angle A. How large is angle A?
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
angle A is seven times as large as angle B: A=7B
Angle C is 30 degrees more than angle A: C=A%2B30
FACT About interior angles of a triangle: A%2BB%2BC=180, measures in degrees
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System of equations for the problem description:
system%28A=7B%2CC=A%2B30%2CA%2BB%2BC=180%29



Question asks for the value of angle A.

First two equations can be expressed as formulas in terms of A.
A%2BA%2F7%2B%28A%2B30%29=180
SOLVE THIS for A first.