his is the case when you are given y as a function of x, and asked to solve for the points where y takes a certain value (often zero). If instead you were given x as a function of y, you could do the same thing, but now your solutions would lie on the y-axis. But for some reason, the convention that people use most often is that y depends on x. Really, though, 'x' and 'y' are just names that could be swapped out for any other symbols.
