Math CentralQuandaries & Queries


Question from Jessica, a parent:

Triangle ABC Angle C is 3 times angle A angle B is 30 degrees less than angle C what are the measurements of the angles
I have the measurements and I have the Equation but I can't figure out quite how to solve it the proper way

Hi Jessica.

This is how I would solve it.

Angle C is three times angle A, so that means A = (1/3) C.
Angle B is 30 degrees less than angle C, so that means B = C - 30

In any triangle, the sum of all three angles is 180 degrees, so A + B + C = 180.

Now you can substitute in for A and B: ( (1/3) C ) + (C - 30) + C = 180.

Solve for C. Use that to find A and B.

Stephen La Rocque.

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