The longer side of a triangle is 3 times the shorter side. The third side is 4 inches longer than the shorter. How long is the short side if the perimeter is more than 39 inches?

Answer 1

If the shortest side is x, then we have

x + (x+4) + 3x > 39
5x > 35
x > 7

By the way, longer implies only two items. You want to use longest here, since a triangle has three sides.

Especially, since without knowing the value of x, maybe x+4 is bigger than 3x. The problem should simply have stated 2nd side and 3rd side.