finding all solutions by factoring x3+x2=20x

Question

finding  solutions to the question 

Answer 1

x^3+x^2=20x

x^3+x^2-20x=0

factor out an "x"

x(x^2+x-20)=0

factor the trinomial

(x+5)(x-4)

the complete factorization is...

x(x+5)(x-4)=0

x=0

x+5=0 ----> x=-5

x-4=0 ----> x=4

the solutions are 0, 4, and -5