How to define the law of sines.
How to define and use the law of cosines.
How the ratio of protons to neutrons affects a nucleus' stability.
How to solve proportions.
How to find the slope of a line if given a graph.
How to solve word problems when 2 people are doing a work job together.
How to calculate the circumference of a circle.
How to find percent yield for chemical experiments.
How to solve word problems involving rates of travel, possibly including wind or water current.
Short, helpful video on ACT prealgebra by top ACT prep instructor, Devorah. Videos are produced by leading online education provider, Brightstorm.