SOLUTION: the function h(t)=-16t^2+32t+128 represents the height of a cannon ball in feet t seconds after it is shot form a cannon. How many seconds does it take the cannonball to hit its ta

Algebra ->  Functions -> SOLUTION: the function h(t)=-16t^2+32t+128 represents the height of a cannon ball in feet t seconds after it is shot form a cannon. How many seconds does it take the cannonball to hit its ta      Log On


   

Question 824742: the function h(t)=-16t^2+32t+128 represents the height of a cannon ball in feet t seconds after it is shot form a cannon. How many seconds does it take the cannonball to hit its target on the ground?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
h(t)=-16t^2+32t+128 represents the height of a cannon ball in feet t seconds after it is shot form a cannon. How many seconds does it take the cannonball to hit its target on the ground?
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Note h(t) = 0 when the ball hits the ground.
Solve for h(t) = 0
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-16t^2 + 32t + 128 = 0
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t^2 -2t -8 = 0
Factor:
(t-4)(t+2) = 0
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time = 4 seconds
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Cheers,
Stan H.
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