Question

A rectangular yard has area 96 square feet. If the width of the yard is 4 ft less than length, what is the perimeter,in feet, of the yard?

Answer 1

x(x-4) = 96
x^2-4x-96=0
(x-12)(x+8)=0
(x-12)=0  or  (x+8)=0
x=12  or  x=-8   -> not x=-8 because you can't have a negative x

12x2 + (12-4)x2 =
24 + 16 = 40