SOLUTION: A projectile is fired upward from a tower 300 feet high with an intial velocity of 320 feet per second. Its height above ground(h feet)is given at any time(t seconds) by the equat

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Question 446304: A projectile is fired upward from a tower 300 feet high with an intial velocity of 320 feet per second. Its height above ground(h feet)is given at any time(t seconds) by the equation: h=-16t^2+320t+300. How many seconds will it take the projectile to reach its maximum height? What is that maximum height?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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A projectile is fired upward from a tower 300 feet high with an initial velocity of 320 feet per second.
Its height above ground(h feet)is given at any time(t seconds) by the equation: h=-16t^2+320t+300.
How many seconds will it take the projectile to reach its maximum height?
:
Use the axis of symmetry formula to find the time for max height: x=-b/(2a)
t = %28-320%29%2F%282%2A-16%29
t = %28-320%29%2F%28-32%29
t = +10 seconds it will be at max height
:
What is that maximum height?
Replace t with 10 in the original equation
h = -16(10^2) + 320(10) + 300
h = -1600 + 3200 + 300
h = 1900 ft is the max height