Which of the following statements best describes the "grouping method" of factoring trinomials?

Choose the correct answer below.

O A. The grouping method of factoring trinomials involves separating the first and last terms of the trinomial into respective factors, and then factoring by

grouping

OB. The grouping method of factoring trinomials involves rewriting the bx term into the factors that fit the particular trinomial, and factoring these four terms using

grouping

OC. The grouping method of factoring trinomials involves factoring out the common factor.

B. The grouping method of factoring trinomials involves rewriting the bx term into the factors that fit the particular trinomial, and factoring these four terms using grouping

Explanation:

The description may be better explained by applying it to an example.

Example:

trinomial: x² - x - 30

the general form of a trinomial is a x² - bx - 30

comparing with x² - x - 30 the bx term is - x

then you must rewrite the bx term, - x, into two terms whose coefficients are factors of 30:

Two numbers which add up - 1 and multipled are - 30. Those numbers are - 6 and + 5, because - 6 + 5 = - 1 and (-6) * (+5) = - 30.

Hence, the two terms are - 6x and 5x, and the expression rewritten is:

x² - 6x + 5x - 30

factor these four terms using grouping:

(x² - 6x) + (5x - 30)

x (x - 6) + 5 (x - 6)

(x - 6) (x + 5)

Hence, the factored trinomial is (x - 6) (x + 5)