Question 23667
I think it probably means different things in different situations.  


For example, the instructions for a set of problems may say "Solve each of the following equations."  Then you will have a list of exercises and you might have a problem that says:  3x+2y =6, for y.  What that means is to take the given equation and solve FOR y.  In other words the "for" tells you what variable to solve FOR.  Does that help?


R^2 at SCC