Question

A triangle has 180 degrees. Two angles of a triangle are the same size. The third angle is 12 degrees smaller than the first two angles. What is the degree of the angles?

Answer 1

The two same-size angles are 64°; the third angle is 52°.

Explanation:

Let x represent each of the same-size angles. Then the smaller angle is (x-12). The sum of angles is 180°, so we have ...

... x + x + (x-12) = 180

... 3x -12 = 180 . . . . . simplify

... x - 4 = 60 . . . . divide by 3

... x = 64 . . . . . . . add 4

... (x-12) = 64-12 = 52 . . . . . find the third angle

The same-size angles are 64°; the third angle is 52°.