The given polynomial is :
[tex]x^{3}+5x^{2}+6x[/tex]
One factor is given as : [tex]x^{2} +3x[/tex] or [tex]x(x+3)[/tex]
So, now solving this for 2nd factor, we get,
[tex]x(x^{2}+5x+6 )[/tex]
[tex]x[(x^{2}+3x+2x+6)][/tex]
[tex]x(x+3)(x+2)[/tex]
Hence, the second factor is (x+2)
