Answer: The correct options are A and D.
Step-by-step explanation:
If we want to find the average rate of change from the beginning of the slide to when the slide has covered a horizontal distance of 15 feet, the we have to find the initial point and point where horizontal distance is 15 feet.
In the given graph x axis represents the horizontal distance and y axis represents the height of the slide.
From the figure it is crealy noticed that the coordinates of the points are (0,80), (5,40), (10,20), (15,10) and (20,5).
Since at the initial point the horizontal distance is 0, so the coordinates of initial point is (0,80).
The coordinates of the point where horizontal distance is 15, are (15,10).
Therefore to find the slope or average rate of from the beginning of the slide to when the slide has covered a horizontal distance of 15 feet the required points are (0,80)and (15,10). So option A and D are correct.