I personally think this is very hard for age 12 and having just finished prealgebra, but I am not mathy.
I'm mathy, and this is way beyond what students in a first-quarter algebra course should be doing. It wouldn't surprise me if a lot of the kids in class are lost.
We have a situation where the books are awful and fear encourages a focus on skills that might be on a high-stakes test. Add to it that teachers, even though they may mean well, don't understand how the subject is learned (and may not fully understand the subject itself). Ergo, they can't teach it. Very few people in the field seem to understand that if you teach the fundamentals, the kids will be able to answer the questions on the bubble tests. It's a Dunning-Kruger thing, I suspect: they don't know how clueless they truly are, and are unaware of the damage they do.
I'm going to go back to my original advice. Start her on a proper pre-algebra course like the one I linked to. If you have a local Mathnasium, they might teach it to her (the Mathnasium was the starting point for my son saying, "Math is my friend again.").
The thought of starting over may seem icky. But try to see it this way: she's not starting over because she never got started properly to begin with.
