How do you factor #-18x ^ { 3} - 8x ^ { 2} + 6x#?

2 Answers
Nov 9, 2017

Extract the variable first into a quadratic and the variable.

Explanation:

#-18x^3 - 8x^2 + 6x = x xx (-18x^2 - 8x + 6)#
#2x xx (-9x^2 - 4x + 3)#

#x = 0# is one solution, the others are found using the quadratic formula on the remaining part of the expression.

Nov 9, 2017

#2x(-9x^2-4x+3)#

Explanation:

You have to factor out the largest factor of every term in the trinomial. It turns out that #2x# factors evenly out of every term.

#2x(-9x^2)+2x(-4x)+2x(3)#

Pulling the #2x# term out to the front gives

#2x(-9x^2-4x+3)#