Question

Factor this trinomial.

х^2 - 9х+ 20
А. (х- 4)(х+ 5)
В. (х-2)(х+ 10)
С. (х-2)(х- 10)
D. (x-4)(х - 5)

Answer 1

(x-4)(x-5)

Explanation:

х^2 - 9х+ 20

What 2 numbers multiply to 20 and add to -9

-4*-5 = 20

-4+-5 = -9

(x-4)(x-5)

Answer 2

D

Explanation:

We're looking for two numbers that have a sum of -9 and a product of 40. These 2 numbers are -4 and -5 so the answer is (x - 4)(x - 5).