SOLUTION: A science teacher is conducting an experiment with a model rocket. The function h=-16t^2+64t models the height of the rocket, where h is the height of the rocket in feet and t is t

Question 1016037: A science teacher is conducting an experiment with a model rocket. The function h=-16t^2+64t models the height of the rocket, where h is the height of the rocket in feet and t is the time in seconds after it is launched. Determine how many seconds the rocket is in the air.
Found 2 solutions by fractalier, macston:
Answer by fractalier(6550) (Show Source): You can put this solution on YOUR website!
A couple of ways to do this, but the simplest may be to solve this equation for when h = 0.
Obviously h = 0 at t = 0, but let's solve for t...
-16t^2 + 64t = 0
-t^2 + 4t = 0
t(4 - t) = 0
t = 0, 4
Time is 4 seconds in the air.
Answer by macston(5194) (Show Source): You can put this solution on YOUR website!
.
Set h=0. The rocket will be at 0 height twice:
once when launched (t=0) and again when it lands.
You want the difference between these two.
.

.
The rocket is launched at 0 seconds and lands at 4 seconds.
.
ANSWER: The rocket is in the air for 4 seconds.
.

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