It's most likely too late for us to help you with anything you need for a final exam today (Jan. 20).
For future reference, I have a couple of suggestions:
1) DO NOT WAIT until the night before a final exam to seek help.
2) Post an example of a specific problem you are having trouble with. We don't "teach" entire topics, such as locus, but can help you understand a problem or two. When you post your problem, tell us exactly how you tried to solve it, showing all of your steps (even if you think you are wrong!) We can best help you if we can see how you are thinking about a problem and what mistakes you might be making.