Question

A rectangle is 3 times as long as it is wide. if the area is 27 square feet, find its perimeter.

Answer 1

w - a width
3w - a length
27 ft² - an area

Therefore:

w · 3w = 27
3w² = 27    |:3
w² = 9 → w = √9 → w = 3

3w = 3 · 3 = 9

width = 3
length = 9

The perimeter:

P = 2 · width + 2 · length

P = 2 · 3 + 2 · 9 = 6 + 18 = 24 ft.