Factor using the ac-method.
-$9 z^{2}+6 z-8$
A) prime
B) $(3 z+4)(3 z-2)$
C) $(3 z-4)(3 z+2)$
D) $(9 z+4)(z-2)$

Question

Quizplus · Accepted Answer

The ac-method involves multiplying 'a' and 'c' (from ax^2+bx+c) and finding two numbers that multiply to ac (-72 in this case) and add to b (6). The numbers 12 and -6 work. Rewrite the middle term using these numbers: $9z^2 + 12z - 6z - 8$. Factor by grouping: $3z(3z+4) - 2(3z+4)$, resulting in $(3z+4)(3z-2)$.

Factor Using the Ac-Method 9z2+6z−89 z^{2}+6 z-89z2+6z−8 A) Prime B) (3z+4)(3z−2)(3 z+4)(3 z-2)(3z+4)(3z−2)

Factor Using the Ac-Method $9 z^{2}+6 z-8$ A) Prime
B) $(3 z+4)(3 z-2)$