Question

a rectangular retaining wall has an area of 15 square feet. the height of the wall is two feet lesss than its length. find the height and the length of the wall.

Answer 1

x(x-2)=15
x^2 - 2x = 15
x^2 - 2x - 15 = 0
(x-5)(x+3)=0
x-5=0 x+3=0
x=5 x=-3

The length is 5 because -3 cannot be the answer as it is negative. The height of the wall is 3 because 5-2 is 3.