Question

Select the two binomials that are factors of this trinomial.

x^2-x-12
A. X+6
B. X-4
C. X-6
D. x + 3

Answer 1

B and D

Explanation:

If you call s=-1 the coefficient of x and p=-12 the constant term, you must find two numbers whose sum is s and product is p.

In this case the two numbers are -4 and +3 in fact:

(-4)+(+3)=-1=s

(-4)*(+3)=-12=p

The polynomial can therefore be written as

(x-4)(x+3)

If you want to check this result, just multiply and get:

(x-4)(x+3)=x^2+3x-4x-12=x^2-x-12

Answer 2

B and D

Explanation:

Given

x² - x - 12

Consider the factors of the constant term (- 12) which sum to give the coefficient of the x- term (- 1)

The factors are - 4 and + 3 , since

- 4 × 3 = - 12 and - 4 + 3 = - 1 , then

x² - x - 12 = (x - 4)(x + 3) ← in factored form