Answer: 60
suppose: the width of a rectangle is x (x > 0)
⇒ The length of a rectangle is 4x
because the area of the rectangle is 144 ft
=> 4x.x = 144
⇔ x² = 144/4 = 36
⇒ x = 6
with x = 6 ⇒ The length of a rectangle is 4.6 = 24
the perimeter of the rectangle is (6 + 24).2 = 60
Explanation: