what is the length of all three sides

Question

A triangle poster has a perimeter of 64 inches. The longest side is 4 inches more than twice the shortest side. The medium length side is 5 inches less than twice the shortest. Find the length of all three sides.

Answer 1

L= 4+ 2S

M = 2S -5

L+M+S = 64

4+2S + 2S-5 + S =64

5S = 64-4+5 = 65

S = 65/5 = 13 inches = shortest side's length

M=26-5 = 21 inches = middle side's length

L=26+4 = 30 inches = longest side's length

30+21+13 = 64