I have the formula: $$PV = C * {{(1-(1+r)^{-n})} \over r}$$
This is the formula for the Present Value (PV) of an Annuity (C) with interest (r) (for example 5% interest is 0.05) over (n) periods.
I would like to rewrite the formula so that I can solve for C. For the life of me I cannot get it right for some reason. I know I could just google the formula, but I want to be able to re-write the formula on my own. Could someone be so kind to show me the steps on how to re-write this?
Hint:
Multiply by $r$ on both sides and then divide by $(1 - (1+r)^{-n})$ on both sides.
Alternate Hint:
Perhaps this might be easier to look at. You could look at this equation as having the form
$$a = xb$$
where $a = PV, b = (1-(1+r)^{-n})/r, x = C$. Solving for $x$ (equivalent to solving for $C$ since $x=C$) just amounts to dividing both sides by $b$. Then you would have $x =a/b$ and could substitute in the appropriate values.