Question

Find the rate of change of its elevation when x=25

Answer 1

Given:

`y=-(1)/(80)x^2+95`

Differentiate with respect to t

`(dy)/(dt)=-(1)/(80)2x((dx)/(dt))`
`(dy)/(dt)=-(1)/(80)2(25)(8)`
`(dy)/(dt)=-5`

The rate of change of elevation when x=25 is decreasing 5 feet/s .