Well, I don't know whether getting a tutor for her is the right thing to do for this subject. But parents do this for other areas of life all the time. Sports, music. It does sound like that she is stuck somewhere in algebra. It may not be a bad idea. Dropping her off to less advanced track seems to be more drastic than getting her up to speed when she is only in trouble for a quarter of the time in a class. She may very well only need to have a breakthrough this one time than do fine without extra help afterwards.