Question

What is the value of x?


3/5

3

6

8

Answer 1

Since those angles (denoted by the red curve) are congruent, one way to think of it is, if we cut the triangle in half horizontally, we get two right triangles, and by Side-Angle-Angle, these triangles are congruent. Any way we justify it, this tells us that the top side and the bottom side are the same length, so
\[2x+5 = 3x+2\]and when we solve it, we get x = 3.