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The measure of one angle, A, of a triangle is 12° more than that of a second angle, B. The third angle, C, is 25° larger than B. One of the three required equations is A + B + C = 180. [Omit units.] Complete the other two equations required to solve for these three angles. Do not simplify or solve these equations.
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The measure of one angle, A, of a triangle is 12° more than that of a second angle, B. ---> A = B + 12
The third angle, C, is 25° larger than B. ---> C = B + 25.