Question

Find the zeros of the polynomial function.

f(x) = x2 + 9x + 20


2, 10
−4, −5
−2, −10
4, 5

Answer 1

first factor the function into the form
(x + a)(x + b) = 0

now find the numbers a and b
a * b must = 20 and a + b must = 9

Answer 2

lets guess 2 numbers which multiply together to give 20
4 and 5 right?

and what do they add up to ?