I need to solve this problem for y:

$\displaystyle e^{-y} + e^x = c$

Ordinarily, I would think this would involve taking ln on both sides, but that doesn't seem to be enough to take me to the final solution, which is:

$\displaystyle y = -ln(c - e^x)$

Can someone remind me how to accomplish this?

EDIT: 5 seconds after I posted this, I realized how to do it. Thanks for reading this, and sorry for the trouble! I would have deleted the thread if I could.