Since the graph shows a proportional relationship, in order to find the unit rate in miles per hour, we just need to choose a point in the graph and divide the number of miles by the number of hours.
Looking at the graph, we can choose the point (2.5, 8), so we have:
[tex]\text{unit rate}=\frac{8\text{ miles}}{2.5\text{ hours}}=3.2\text{ miles/hour}[/tex]
So the unit rate is 3.2 miles per hour.
