. A rectangular banner has a length that is two feet shorter than twice its height, h. If the expression represents the area of the banner is shown below, what is the height of the banner whose area is 60

Respuesta :

Answer:

height h = 6 ft

Step-by-step explanation:

Given;

Area = 60 ft^2

length l that is two feet shorter than twice its height, h.

Length l = 2h - 2

Area = length × height = l × h = 60

Substituting l = 2h - 2

(2h-2) × h = 60

2h^2 - 2h = 60

Divide through by 2,

h^2 - h - 30 = 0

Solving the quadratic equation, we have;

(h-6)(h+5) = 0

h = 6 or h = -5

Since h cannot be negative;

height h = 6 ft