A vertical line has an undefined slope since it would result. The topic of this set of preliminary notes is the Cartesian coordinate system and related topics. To find the slope you divide the difference of the y-coordinates of 2 points on a line by the difference of the x-coordinates of those same 2 points.
Solving for Slope 1.
Determine if the slope if positive increasing or negative decreasing Step Two. Step 2 Calculate the rise and run You can draw it on the graph if it helps. Using two points on the line calculate the rise and the run and express it as a fraction rise over run. Now to find the equation of the line.