Hello there first-time poster here!

First of all, my apologies if this is the wrong forum to post in, my question pertains to a computer science math class, but I'm not quite sure which discipline of math it falls under.

Anywho, my question is, how can you solve for a non-integer number base, given everything but said base itself?

I have a number in base 10, (84) and a number in base b (234) and I have to solve for b. 84_{10}= 234_{b }

If anyone could point me in the right direction on how to solve this, I would be very thankful.

Thank you in advance!