Question

The length of a rectangle is four times its width.

If the area of the rectangle is 144 cm^2 , find its perimeter.

Answer 1

Let width of rectangle be x cm.

Width = x cm

Length = 4x cm

Area of rectangle = length x width

4x × x = 144

4x² = 144

x² = 144 ÷ 4 = 36

x = √36 = 6

Width = 6 cm

Length = 6 × 4 = 24cm

Perimeter = 6 + 24 + 6 + 24 = 60 cm