Review everything you did in Algebra I, and take it up a notch. You definitely should be way past system of equations, inequalities, functions(slope and quadratic), and absolute value. Being comfortable with the simple things like integers, mental math ect. can also extend your knowledge, and can save a lot more time. Also its important to be very very very very very comfortable in graphing, the sections ( x,y – -x,-y ) and easily spotting zeroes and slope on graphs and equations