I have a physics problem that the solution requires the division of one equation by another equation. It is just a question about the ideal gas law and finding final pressure as temperature and volume change.

My question is in what general cases does an algebra problem require the division operation? Or, more generally, what typical question or phrase might I look for to tell me that I should consider using some operation to combine equations?

A link would be sufficient, I just haven't found anything to answer my questions.

Thanks for information.