I guess they are kind of synonymous depending on the context. So both are correct without further context.
to find an answer to a problem:to solve a problem
to solve a mystery/puzzle
Just calm down - shouting won't solve anything!
This strategy could cause more problems than it solves.
Police are still no nearer to solving the crime."
to solve or end a problem or difficulty:
Have you resolved the problem of transport yet?
The couple resolved their differences and made an effort to get along."
Student or Learner