Factor.
-$12 x ^ { 2 } - 52 x - 40$
A) $4 ( 3 x + 2 ) ( x - 5 )$
B) $( 12 x + 8 ) ( x - 5 )$
C) $4 ( 3 x - 2 ) ( x + 5 )$
D) $( 3 x + 2 ) ( 4 x - 20 )$

Question

Quizplus · Accepted Answer

To factor, we need to find two numbers whose product is -480 (the product of the first and last coefficients) and whose sum is -52 (the coefficient of the x-term). The numbers are -20 and 24. Using these numbers, we can rewrite the expression as:
$$12x^2-52x-40=12x^2-20x+24x-40=4(3x+2)(x-5)$$ 
Therefore, the correct answer is A.

Factor - 12x2−52x−4012 x ^ { 2 } - 52 x - 4012x2−52x−40

Factor
- $12 x ^ { 2 } - 52 x - 40$