Which method would be the best to solve the following system of equations? Graphing
Substitution
Elimination
None of these methods will work.

Element x decays radioactively with a half life of 8 minutes. if there are 450 grams of element x, how long, to the nearest tenth of a minute, would it take the element to decay to 37 grams?

Given a(-12,5) and b(12,29) find the point that divides the line segment ab three-eighths of the way from a to b

Find the cosine function that is represented in the graph.