All you need to do is to calculate the difference in the y coordinates of the 2 points and divide that by the difference of the x coordinates of the points rise over run. Once you figure out that you substitute 4 for fx you solve this as a regular two step equation. Plug in these values to the slope formula to find the slope.
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.
You cant find the slope of a. Make sure that the line is straight. Simplify the fraction if possible. Finding the Slope with Two Points 1.