The length of a rectangle is four times it’s width. If the perimeter of the rectangle is 70ft, find it’s area.

Answer 1

L=Length W=Width

Rectangle perimeter: 2L+2W

L=4W

Plug it in for L:

2(4W)+2W=70

Simplify

8W+2W=70

10W=70

Divide both sides by 10 to get W alone

10W/10=70/10

W=7

Now we have

W=7 L= 4W which is 4(7)= 28

Area= L x W

Plug in L and W

28 x 4 = 112

Area of this rectangle is 112