Generelly people who struggle with math are forgeting the basics of what they're learning off of. So go back a few chapters. If you're REALLY falling behind, drop your language and take it in college during the summer(this costs a bit, but I'm doing it to to get ahead and take calc.[That's a really long story, and I literally had no other choice because my school fucked up the course selection sheets.]) or summer-school if it's offered.
7th grade is essentially a review of Gr.6 + a few extra concepts.
8th grade : All I remember is the intro to factoring(and there really isn't too much of it)
9th grade : -.- I don't think we did anything in this grade. Graphing?
10th grade : Linear Algebra and some linear and bilinear graphing. Equation of a line(indirect and direct variation formulas). Inequalities too, but just simple stuff.
11th grade : Parabola, solving system of equations(using elimination and substitution). Graphics inequalities, absolute value. Analyzing shapes and circle geometry(this was moved to a lower grade though.). Hardly any trig. I guess and intro to radicals, that it though :/
12th grade : Preperation for calculus(Taking it this semester).
Depending on how far your into the course, a 10% can be bad or absolutely horrible. It's easy to raise a mark to a pass, but if you want an A you better hope you've only messed up a very small test.
So yeah, I would say go back a couple chapters and review the concepts. Getting someone else to do the work defeats the purpose of ever taking the course.
If I had an MSN I'd give it to you, and you can ask me some math questions. But I don't. Google Math IRC and there are a bunch of losers lingering the channel waiting for someone to ask a math question(though I can't say they'll explain it in a way you understand. You need to tell the what you know so they can use the methods you know to solve the problem.) They tried to help me solve a VennDiagram word problem using matrices D: I was like, wtf.