(x^3 -7x^2 -17x-9)/(x+1)

(x^3 -7x^2 -17x-9)/(x+1)

x^2 * (x+1)=x^3+x^2

x^3-7x^2-17x-9-x^3-x^2

=-8x^2-17x-9

(x+1)(-8x)=-8x^2-8x

=-8x^2-17x-9-8x^2-8x

=-9x-9

(x+1)(-9)=-9x-9

=-9x-9-9x-9=0

answer=x^2-8x-9