http://s777.photobucket.com/albums/y...napshot-99.pngHow do I find the slope ?

Remember that slope is "rise over run." Pick two points on the line; let's call them (x1,y1) and (x2,y2). The amount the line rises between those two points is the difference in y coordinates: y2-y1. And the "run" is the difference between the x coordinates of the two points: x2-x1. Hence the slope is: (y2-y1)/(x2-x1). For a straight line on a graph it does not matter which two points you pick - you should always get the same answer (since the slope is constant for a straight line).