Answer:
[tex]\frac{-75ft}{30sec}[/tex] or simplified would be [tex]\frac{-2.5ft}{sec}[/tex]
Step-by-step explanation:
In order to calculate the rate of change, we must subtract his end position and end time by the starting position and starting time. We are using the -15 feet since it is below the surface area as the starting position and the 10 seconds as the starting time. We make each of these into a fraction and subtract like so...
[tex]\frac{-90ft - (-15ft)}{40sec - 10sec} =[/tex] rate of change
[tex]\frac{-75ft}{30sec} =[/tex] rate of change
[tex]\frac{-2.5ft}{sec}[/tex] = rate of change
Therefore, we can see that the rate of change of the diver is [tex]\frac{-75ft}{30sec}[/tex] or simplified would be [tex]\frac{-2.5ft}{sec}[/tex]