Graph y = -x + 3 (Using Slope-Intercept Form)

In this video, we'll use slope-intercept form to draw the graph for y = -x + 3. You may also see this written as f(x) = -x + 3.

y = -x + 3 (already in slope-intercept form).

b tells us where the graph crosses the y-axis. That gives us our first point for the graph.

m is the slope. We can use the slope to find the rise over run. For -1, we consider that to be -1/1. So we go down one on the y-axis and over 1 on the x-axis. We can do that as many times as we need to in order to draw an accurate line.

I prefer to use the slope-intercept formula since it is much quicker with some practice. You could also use a table of values to make sure the points fall on the line. If they don’t, there is likely a problem. When graphing equations, it is helpful to have them in slope-intercept form (y = mx + b), just like we have in this video.