Answer: $$x(x+4)(x+3)=x(x^2+7x+12)=x^3+7x^2+12x$$.
Explanation:
In general, if you want
x
=
c
to be a root of a polynomial, then the polynomial must contain at least one factor of the form
x
โ
c
(if
c
<
0
the
x
โ
c
can be written as an addition of a positive number).