Answer
$x=0$ or $x=2$ or $x=-2$
Work Step by Step
$ x^{3}-4x=0\qquad$...factor out the common term, $x$.
$ x(x^{2}-4)=0\qquad$...recognize a difference of two squares:
$a^{2}-b^{2}=(a-b)(a+b)$
$ x(x-2)(x+2)=0\qquad$...apply the principle of zero products.
$x=0$
$x-2=0$
$x=2$
$x+2=0$
$x=-2$
Type the equation into a graphing utility and see
that the graph intercepts the x-axis at $0,2$ and $-2$.
