Question

A rectangle is 20 feet longer than twice its width. If its perimeter is 520 feet, find the length and the width.

Answer 1

L= length. w= width. Perimeter of rectangle= 2(length) + 2(width). 520= 2L+2w. It's say that length is 20 feet plus 2 times it's width. L=(20+2w). Replacing L on equation. 520= 2(20+2w)+2w. 520 =40 +4w +2w. 480=6w. 80=w.width is equal to 80 feets, replace width on first equation to get the length. 520 =2L + 160. 360=2L. 180=L. Length is equal to 180 feets.

Answer 2

`520=2(length)+2(width) \\ 520=2(20+2w)+2(w) \\ 520=(40+4w)+2(w) \\ 520=(40+6w) \\ 480=6w \\ w=80 \\ length=2(80*2)+20 \\ length=180 \\ width=80`