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

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Answer 1 · 2017-11-09T04:24:25

Extract the variable first into a quadratic and the variable.

#-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.

Answer 2 · 2017-11-09T04:43:59

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

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)#