Question

The height of a pebble dropped from a cliff 20,00 feet heigh is described by formula h(t)=20,000 + 5t^2. How long will the pebble take to reach a height of 32,500 feet?

Answer 1

Answer:

It will take 50 seconds for the pebble to reach the height

Step-by-step explanation:

To calculate the time, simple substitute h(t) for 32,500

So we have

32,500 = 20,000 + 5t^2

5t^2 = 32,500-20,000

5t^2 = 12500

t^2 = 12500/5

t^2 = 2500

t = square root of 2500

t = 50 seconds