Area = length x width
Length = x
Width = x - 7
Area = 8
8 = (x)(x - 7)
8 = x^2 - 7x
x^2 - 7x - 8 = 0
Use the quadratic equation or factor (factoring is shown):
(x - 8)(x + 1) = 0
x - 8 = 0
x = 8
x + 1 = 0
x = -1
Since length is always a scalar quantity, or is always positive, the length is 8 units.
Length = x = 8 units
Width = x - 7 = 1 units
Hope this helps!! :)
