The perimeter of a triangle is 42 inches. One side measures 18 inches. The shortest side measures x inches. The longest side measures 1 inch less than four times the length of the shortest side. Write and solve an equation to find the length of the longest side.
Shortest side = x, Longest Side = 4x-1, third side = 18
Equation is x + (4x-1) + 18 = 42 so 5x-1 = 42-18=24 and 5x=25 so x = 5, longest side = 4(5)-1=19, third side=18
Add all 3 (5+19+18) to get 42
