(x^3 -3x^2 -9x)/(x-5)

(x^3 -3x^2 -9x)/(x-5)

=x^2(x-5)=x^3-5x

=x^3-3x^2-9x-x^3+5x^2

=2x^2-9x

=2x(x-5)=2x^2-10x

=2x^2-9x-2x^2+10x=x

=+1(x-5)=x-5

=x-x+5 remainder

Answer=x^2+2x+1 r. 5