Given:
A rocket is 1.5 miles above the earth in 20 seconds.
It is 8 miles above the earth in 2 minutes.
To find:
The rockets rate of change in miles per seconds.
Solution:
Let y be the height above the earth after x seconds.
A rocket is 1.5 miles above the earth in 20 seconds. So, the point is (20,1.5).
It is 8 miles above the earth in 2 minutes.
1 minute = 60 seconds
2 minutes = 120 seconds
So, the point is (120,8).
The rockets rate of change in miles per seconds is




Therefore, the rockets rate of change is 0.065 miles per seconds .