Start off with your slope formula which is shown at the top of the image.
Then, plug your appropriate values in for x1, y1, x2, and y2.
Then, remember that minus a negative means plus a positive.
After you simplify the top and bottom, you end up with -8/6.
Notice that -8/6 reduces to -4/3.
So the slope of the line that passes through the given points is -4/3.