SOLUTION: In one of the early rocket experiments on The Planet of the Apes, a banana was launched straight upward so that its height in feet above the ground after t seconds was given by the

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: In one of the early rocket experiments on The Planet of the Apes, a banana was launched straight upward so that its height in feet above the ground after t seconds was given by the      Log On


   

Question 18112: In one of the early rocket experiments on The Planet of the Apes, a banana was launched straight upward so that its height in feet above the ground after t seconds was given by the function h= -42t^2+504t. When did the banana hit the ground?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Ok, using your function...h%28t%29+=+-42t%5E2+%2B+504t, you are really asking the question...at what time, t, is the height of the banana equal to zero.
To find the answer to this question, we'll just set the function equal to zero and solve for t.
-42t%5E2+%2B504t+=+0 Factor out a -42t to simplify processing.
-42t%28t+-+12%29+=+0 Now apply the zero products principle.
-42t+=+0 and/or t+-+12+=+0
If -42t+=+0, then t = 0 This is the initial state or the time at which the banana was launched.
If t+-+12+=+0, then t = 12 seconds. This is when the banana reaches the ground again.