Solving equations: x^3 - 9x = 0

[sai]

I am trying to solve the following equation please tell if I am on the right track.

Problem
x^3-9x=0

(x^3-9x)=0
x(x^2-9)=0
x(x-3)(x+3)=0
x=0//x-3=0//x+3=0
+3 +3 -3 -3
x=3 x=-3
Answer x= 3, -3

 

[stapel]

What happened to "x = 0"?

Eliz.

 

[sai]

Solving equations

I am not sure. What did I do wrong?

 

[stapel]

Re: Solving equations

What did I do wrong?

Look back in your steps. You had three factors at one point. One of them disappeared, taking a solution with it.

Eliz.