Steve starts at home when the time is x = 0 minutes. The y value y = 40 pairs up with this x value. This is shown by the point (0,40) on the diagonal line, aka the y intercept. The y intercept is where the line crosses the y axis.
The y = 40 indicates that Steve has 40 miles remaining when he starts at home. In other words, the distance from home to work is 40 miles.
The x intercept is where the diagonal line crosses or touches the x axis. The x intercept is (45,0) which represents the idea that 45 minutes have passed by. The y = 0 means that he has 0 miles left go to. Steve has reached the office at this point.
