How to find x?

1. Feb 10, 2008

ytpj

1. The problem statement, all variables and given/known data
$$\frac{2-x}{2+x}=t^3$$
How to find x?

$$x=\frac{2-2t^3}{1+t^3}$$

2. Feb 10, 2008

quasar987

Start by multiplying both sides of the equation by (x+2).

3. Feb 10, 2008

CompuChip

Reminds me of this very old one

(but seriously, do what quasar987 told you)

4. Feb 10, 2008

ytpj

I don't understand where this leading. It still will be
$$2-x=2t^3+xt^3$$ so what?

5. Feb 10, 2008

quasar987

Then send everything on the same side of the equation so that you get

$$2-x-2t^3+xt^3=0$$

and factor the x.