1. Lets say that you get the coords. (1,2). X would be the first one (1), and Y would be the second number (2). if you got 2/1, then, because of rise/run, that 2 would be Y and 1 would be X
2. ? don't know
3. Slope is rise/run (Y/X), and the Y intercept is where the line intercepts the Y axis.
