Question

The length of a rectangle is one inch less than three times it's width. If the perimeter of the rectangle is 54 inches, find the length.

Answer 1

l = 20

Explanation:

set up a system of equations

l = 3w -1

54 = 2l + 2w

substitute

54 = 2(3w-1) + 2w

56 = 8w

w = 7

l = 3 *7 -1

l = 20