Question 742494
When a root is at x=a then the factor is x-a.  So for x=-6 the factor is x+6, and for x=-1 the factor is x+1.  Multiplicity 3 means there are three factors (x+1).<P>
Multiply the factors together to see the polynomial.<P>
(x+6)(x+1)(x+1)(x+1) = {{{(x+6)(x^3+3*x^2+3*x+1) = x^4+9*x^3+21*x^2+19*x+6}}}