Expert: Steve Holleran - 4/18/2007

Question
factor
2x^3+11x^2+5x=0

Answer
Hi Angelo,

When you do your factoring, ALWAYS look to take out a common factor first.  Here, we can factor out an "x":

  2x^3 + 11x^2 + 5x = x ( 2x^2 + 11x + 5)= 0

Now factor the parenthesis:

     2x^2 + 11x + 5 =   (2x +  )(x +   )

Now, you have to use 1 and 5 for the other numbers in each factor, and since you want the middle term to be 11x, the 5 has to be in position to multiply the 2x, so it goes:

                      = (2x + 1)(x + 5)

So now your equation looks like:

            x * (2x + 1)(x + 5) = 0

and the solutions are x = 0 , -1/2 , -5.

Hope this helps out.

Steve Holleran