Question

A rectangular retaining wall has an area of 36 square feet. The height of the wall is 5 feet less than it’s length. Find the height and length of the wall in feet.

Answer 1

Length = 9 feet

Height = 4 feet

Explanation:

Length = x

Height = x-5

36 = (x-5) * x

36 = x^2 - 5x

0 = x^2 - 5x - 36

Find the zeroes of the equation:

`x^2-5x-36`

We get:

`x= -4;\ x=9`

Since length cannot be negative, we choose "x = 9"

Therefore,

Length = x = 9

Height = x - 5 = 4