Question

The length of a rectangle is 5 units more than the width. The area of the rectangle is 36 square units. What is the length, in units, of the rectangle?

Answer 1

Explanation:

Area = length times width

w = width

length = w + 5

Area = 36

w(w +5) = 36

w² + 5w = 36

w² + 5w - 36 = 0

Factor

(w + 9)(w -4) = 0

solve each root

w + 9 = 0

w + 9 - 9 = 0 - 9

w = -9

w - 4 = 0

w -4 +4 = 0 + 4

w = 4

The two roots to the equation are -9, 4.

-9 is not an answer to the problem, as it makes no sense. But 4 is an actual root.

the length is 5 + 4 = 9

So the length is 9 units.