Question

Suppose you have 36 yards of fencing to build a fence around a rectangular backyard garden. The width is 18 yards less than twice the length. Find the length and width of this garden.
rbowh
l = length
w = width = 2l - 18

P = 2l + 2w
36 = 2l + 2(2l - 18)

Can you solve from here?