The length of a rectangle is 1 foot less than twice the width, and the area of the rectangle is 21 ft.². Find the dimensions of the rectangle

Answer 1

w (2w-1) = 21

2 w^2 - w - 21 = 0

(2 w -7)(w+3) = 0

w = 7/2 = 3.5

then L = 6

Answer 2

Mr. Yau uses 88m of fence to enclose 384m^2 of a rectangle plot of lawn. Find the dimensions of the lawn.