hi, i've done part of a question that i need help finishing. the question is:

use the factor theorem to show that $\displaystyle (x - 2)$ is a factor of $\displaystyle P(x) = x^3 - 3x^2 - 4x + 12$ (which i did)

then it says:

write P(x) as a product of three linear factors.

now obviously (x - 2) is one of them so i found out what the equation was that had to be multiplied by (x - 2) to get $\displaystyle P(x) = x^3 - 3x^2 - 4x + 12$ and i came to $\displaystyle (x^2 - x -6)$ and tried to factorise it further but couldn't. why can't i find two numbers that multiply to give -6 but add to give -1? surely this is the way to do it?

thanks, mark