Problema Solution

The first angle of a triangle is 4 degrees less than twice the second angle. The third angle is 25 degrees more than the second angle. What is the measure of the first angle?

Answer provided by our tutors

Second angle = x

First angle = 2x - 4

Third angle: x + 25

Their sum is 180, so

x + 2x - 4 + x + 25 = 180

4x + 21 = 180

4x = 159

x = 39.75

First angle = 2x - 4 = 2(39.75) - 4 = 79.5 - 4 = 75.5 degrees