Your daughter is only in 10th grade and got a good SAT score. What is the SAT score that you are hoping that she will eventually get? I would say that a jump in score by 140 or so points is pretty good.
FWIW, I just read an interesting book called “How To Be A High School Superstar,” by Cal Newport. It has some useful suggestions on how to improve your grades, better & more useful study habits other than just rote review, along with how to improve your SAT scores.
Don’t spend any more money on expensive SAT test prep classes. Buy some books that have sample SAT tests in them and have her practice those…and review the questions that she gets wrong so she can re-learn the concepts that she struggles with.
Then maybe have her take the SAT again at the END of 10th grade and see how things improve. If her SAT verbal score needs to be higher, then she should read a lot…for fun, not just for school. That’s a great way to improve your vocabulary.
Try not to stress out about it. Maybe she just needs some extra help in the math department. Is she really skipping a year on math by being in the precalc honors class? If so, maybe it’s too much for her at this point, in which case it would be far better to move down to a math class that is achievable rather than set her up for failure. Your daughter is likely doing the best that she can. Yelling at her might not necessarily be the best solution to the problem. Try looking at it from a problem-solving point of view instead of looking at it as if your daughter isn’t working hard enough or trying hard enough.
Re: her eating habits & weight - exercise can often be a useful way to relieve stress. Perhaps there’s a physical activity that she’d like to get involved in that would help in that department?