Question

Consider the polynomial function.

f(x)=-2(x-5)(x+6)(x+7)
which zeros can be used to graph the polynomial function?

a.) x=-7, -6, and 5
b.) x=-7, -6, -2, and 5
c.) x=-5, 6, and 7
d.) x=-5, -2, 6, and 7

Answer 1

a

Explanation:

to find the zeroes let f(x) = 0 , that is

- 2(x - 5)(x + 6)(x + 7) = 0

equate each factor to zero and solve for x

obviously multiplying any value by - 2 will not give zero

so only consider the binomial factors

x + 7 = 0 ⇒ x = - 7

x + 6 = 0 ⇒ x = - 6

x - 5 = 0 ⇒ x = 5