This link is a website that summaries the ambiguous case scenarios for the law of sines. Try remember the information with the least amount of memorization.
Look under Integrated 2 Mr. Ochoa under class files to located the review material for your Final. Don't forget to study notes, formulas, and other quizzes that were returned to you. Good luck!
Problem 4A is a bit different than the handout i gave you. If your numerator is an opposite sign it is because the third term is different from the problem i gave you.