Question

What is the factored form of the polynomial?

x2 + 9x +20
A. (x - 4)(x - 5)
B.(x-2)(x - 10)
C.(x + 4)(x+5)
D.(x + 2)(x + 10)

Answer 1

C. (x + 4)(x + 5).

Explanation:

We need 2 numbers whose product is + 20 and whose sum is + 9.

They are + 5 and + 4 , so

x2 + 9x +20

= (x + 4)(x + 5).