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
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
[tex]m=\dfrac{8-1.5}{120-20}[/tex]
[tex]m=\dfrac{6.5}{100}[/tex]
[tex]m=0.065[/tex]
Therefore, the rockets rate of change is 0.065 miles per seconds .