Answer:
When you're given a line, you can find the rise over the run also known as the slope using a graph, calculating it using the formula, or using a table with two points you've been given from the line. Once you find the slope find the y-intercept which is the point at which the line intercepts with the y-axis of the cartesian plane. I also added some attachments of my own work and an explanation of slope.
Hope I helped have a nice day :)