I have reduced an equasion down to as small as I can get it, need a little help solving the rest..

I need to solve for 'm'..

What I have right now is this:

$\displaystyle -19500 = -{\ln(1+52000m)\over m}$

This is based off of known numerals of the original equasion, which may also be solved for 'm' but I couldn't do it myself (again, ln is messing me up here...)

$\displaystyle t = r(x - {\ln(1 + mx)\over m})$

Solving either one is good enough for me. Even when I tried an online tool to solve for 'm' it said 'impossible'. Somehow I don't know why that would be impossible, because then the only other way to solve for 'm' would merely be to 'guess my way to it', and of course, that's just bs...

Thanks again, my math problems for a while now are pretty well done after this one...