Question 1065794
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You are given

A = B = 2.5C,

where A and B are two congruent angles at the base and C is the vertex angle.


Then A + B + C = 2.5C + 2.5C + C = 6C = 180 degrees.

Hence, C = {{{180/6}}} = 30 degrees.

Then A = B = 2.5*30 = 75 degrees.
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