Question

Factor each trinomial. Then match the polynomial (term) on the left with its factored form (definition) on the right.

Match Term Definition
_____ x2 – 8x – 20 A) (x – 5)(x + 4)
_____ x2 + 8x – 20 B) (x – 10)(x + 2)
_____ x2 – x – 20 C) Prime
_____ x2 – 9x – 20 D) (x – 2)(x + 10)

Answer 1

The answer is B, D, A, C.

1.
`x^(2) -8x-20= x^(2) +2x-10x-2*10= (x^(2) +2x)-(10x+2*10)= \\ =x(x+2)-10(x+2)=(x+2)(x-10)` (choice B)
2.
`x^(2) +8x-20= x^(2) +10x-2x-2*10=( x^(2) -2x)+(10x-2*10)= \\=x(x-2)+10(x-2)=(x-2)(x+10)` (choice D)
3.
`x^(2) -x-20= x^(2) -5x+4x-4*5= (x^(2) -5x)+(4x-4*5) = \\ =x(x-5)+4(x-5)=(x-5)(x+4)` (choice A)
4. This leaves the choice C.