What are the answers to this math problem

4x^3 = 100x

There should be three answers, I believe.

you should subtract 100x from both sides to get:
4x^3-100x. factor out an x
x(4x^2-100). this tell us x is one zero. now lets find where 4x^2-100=0. solve
4x^2=100
x^2=25
x=+ or -5 .
this means that 0 5 and -5 are all correct answers

4x^3-100x = 4x(x+5)(x-5)
solutions are x = 0, +5, -5