the length of a rectangle is four times its width. If the area of the rectangle is 400yd^2, find its perimeter.

100yd

Step-by-step explanation:

Let the width of the rectangle be x yd

Length will be 4x yd

Area = Length * width

400yd² = 4x (x)

4x² = 400yd²

Dividing by 4 throughout gives;

x² = 100, x = 10yd

So x (width) = 10yd

Length = 4 (10) = 40yd

Perimeter = 2 (length + width)

Perimeter = 2 (40 + 10) = 2 (50) 100yd