How do I do this I don’t understand it

Step-by-step explanation:

In order to find slope, first you must find two different points on the line. In this case, they are (0, 0) and (4, 3). Rise is the change in the Y value between the two points. Run is the change in the X value between the two points. (0, 0) goes up 3 and over 4 to become (4, 3). Therefore, the slope of the line is

Keep in mind that when finding slope, you go from left to right, so there are negative slopes, and I assume you'll be getting into those soon!