Question

On the left triangle, the shorter side is labeled 4 inches and the longer side is labeled 10 inches. On the right triangle, the shorter side is labeled x inches and the longer side is labeled 20 inches.

The two triangles above are similar. Find the value of x. Be sure to explain your steps.

Answer 1

clearly, everything on the big triangle is 2 times the corresponding value on the smaller triangle. That's what "similar" means.

Answer 2

4/X = 10/20.