You have 54 feet of trim for a swimming pool that you are installing. You know that twice the width of the pool is 3 feet more than the length. What is the size of the pool?

To get the size of the pool we proceed as follows:

let the width be w

the length will be 2w-3

thus given that the perimeter is 54 ft then the dimensions of the pool will be:

P=2 (L+W)

thus

54=2[ (2w-3) + w]

54=2 (3w-3)

54=6w-6

54+2=6w

hence

60=6w

w=10

hence

length = 2 (10) - 3=17

width=10