SOLUTION: A model rocket is launched upward with an initial velocity of 270 feet per second. The height, in feet, of the rocket t seconds after the launch is given by h = −16t2 + 270t. H

Question 1207285: A model rocket is launched upward with an initial velocity of 270 feet per second. The height, in feet, of the rocket t seconds after the launch is given by
h = −16t2 + 270t.
How many seconds after the launch will the rocket be 390 feet above the ground? Round to the nearest tenth of a second.
Answer by MathLover1(20849) (Show Source): You can put this solution on YOUR website!

Now, we have to find out the time when feet.

or

answer is:
the rocket will be feet above the ground
in seconds on the way up, and
in seconds on the way down

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