Answer:
C
Step-by-step explanation:
The vertex lies on the axis of symmetry which is located at the midpoint of the zeros.
Given
f(x) = (x - 8)(x - 4)
To find the zeros let f(x) = 0, that is
(x - 8)(x - 4) = 0
Equate each factor to zero and solve for x
x - 8 = 0 ⇒ x = 8
x - 4 = 0 ⇒ x = 4
Thus
[tex]x_{vertex}[/tex] = [tex]\frac{8+4}{2}[/tex] = [tex]\frac{12}{2}[/tex] = 6
Substitute x = 6 into f(x) for corresponding y- coordinate of vertex
f(6) = (6 - 8)(6 - 4) = (- 2)(2) = - 4
Vertex = (6, - 4 ) → C
