Factor the polynomial by grouping.
-$12 x ^ { 2 } - 15 x - 16 x + 20$
A) $( 12 x + 4 ) ( x + 5 )$
B) $( 12 x - 4 ) ( x - 5 )$
C) $( 3 x - 4 ) ( 4 x - 5 )$
D) $( 3 x + 4 ) ( 4 x + 5 )$

Question

Quizplus · Accepted Answer

First, group the terms: $12x^2 - 15x - 16x + 20 = (12x^2 - 15x) - (16x - 20)$. Factoring out the greatest common factor from each group gives $3x(4x - 5) - 4(4x - 5)$. Notice that $4x - 5$ is a common factor, so the expression can be factored as $(3x - 4)(4x - 5)$.

Factor the Polynomial by Grouping 12x2−15x−16x+2012 x ^ { 2 } - 15 x - 16 x + 2012x2−15x−16x+20

Factor the Polynomial by Grouping $12 x ^ { 2 } - 15 x - 16 x + 20$