Slope of a graph is the rate of change. In other words we can say a slope is rise over run. How many units graph goes up over how many units graph goes down.
With respect to given problem, we are given:
Tracie’s bus travels towards her home at the speed = 1/2 mile per minute.
Therefore, slope of the speed of Tracie’s bus towards her home is 1/2.
If Tracie’s bus travels towards her home at an average speed = 2 mile per minute then slope would be 2.
Tracie’s bus travels away from her home at an average speed. So the first slope could be 1/2.
And if Tracie’s bus travels away from her home at an average speed of 2 miles per minute the slope would be 2.