Question

The length of a rectangle is six times its width. If the area of the rectangle is 486 in 2 , find its perimeter.

Answer 1

w - width

6w - length

486 in² - area of the rectangle

(w)(6w) = 6w² - area of the rectangle

The equation:

6w² = 486     divide both sides by 6

w² = 81 → w = √81

w = 9 in

l = 6w → l = (6)(9) → l = 54 in

The perimeter: P = 2l + 2w

P = 2(54) + 2(9) = 108 + 18 = 126 in

Answer: The perimeter is 126in