Can you take muscle relaxers and ibuprofen together?

Since you have not identified the "muscle relaxer" you plan to take with ibuprofen, it would not be appropriate to attempt a broad-brush answer here.

You're advised to get in touch with your pharmacist or prescriber (if either of your drugs are prescription-only) to get a more specific answer to your question. Be sure to clearly identify your medication before you call, so you don't have to scramble while somebody's waiting to answer your question.