M.
I know if this was me, the first thing I would say is "are you crazy??!!", but it might be best to try to have a conversation with Lexy, Try to understand exactly what she "hates" about school. Could she have a learning disability? Maybe she is not challenged enough? Listen to what she has to say without interruption. Validate her feelings, but also advise her that dropping out is not a great option. You do not say if she is under your care or not, but if she is and she decides to drop out, I would work with her on developing a success plan. Find out what her goals and aspirations are. Then help her find out what she needs to do to obtain those goals. Give her a deadline for obtaining her GED, then when that is done, give her a deadline for finding a job.
Also telling her honestly how you feel about dropping out might help. Try telling her to take things day by day. See if she would be willing to at least finish this semester and re-evaluate after this sememster. Maybe there is another fun thing she would like to do as an alternative to cheering? Maybe gymnastics or some kind of dance class. Maybe you could tell her if she stays in school, you will help her get involved in another activity of her choice.
Good luck this is a hard situation!