The length of a rectangular driveway is four feet less than five times the width. The area is 672 feet squared. Find the width and length of the driveway

Respuesta :

Answer: length of the drive way = 56 feet

Width of the driveway = 12 feet

Step-by-step explanation:

The rectangular driveway has two equal lengths and two equal widths. The area of the driveway is expressed as

length,l × width,w

The area is 672 feet squared. It means that

L×W = 672

The length of the rectangular driveway is four feet less than five times the width. It means that

L = 5W - 4

Substituting L = 5W - 4 into LW = 672

W(5W - 4) = 672

5W^2 - 4W - 672 = 0

5W^2 + 56W - 60W - 672 = 0

W(5W + 56) - 12(5W + 56) = 0

(W - 12)(5W + 56) = 0

W - 12 = 0 or 5W + 56 = 0

W = 12 or 5W = -56

W= 12 or W = - 56/5

The Width cannot be negative , so

W = 12

LW = 672

12L = 672

L = 672/12 = 56