contestada

The width of a rectangle is 4 units less than the length. The area of the rectangle is 45 units. What is the width, in units, of the rectangle?

Respuesta :

altavistard

Answer:

5 units

Step-by-step explanation:

Represent the length and width by L and W.  Then W = L - 4.

The area of the rectangle is 45 square units = L(L - 4), or

L^2 - 4L - 45 = 0

This factors easily into

(L - 9)(L + 5) = 0, so L must be 9.  We ignore the negative value -5.

The width of the rectangle is W = L - 4, or 5 units.