SOLUTION: Hello, could you please help me with this word problem: Pirates are attacking the Caribbean Island of Nevis! Soliders manning a coastal fortress rush to their cannons their cannon

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Question 1014279: Hello, could you please help me with this word problem: Pirates are attacking the Caribbean Island of Nevis! Soliders manning a coastal fortress rush to their cannons their cannons and prepare to defend the port by sinking the pirate ship. Geoger and Edward are manning a cannon that sits 50 feet above the water in a fortress tower. They load, aim, and fire their cannon. The cannon ball has an initial vertical velocity of 72 feet per second and hits the pirate ship ten feet above the water line exactly 5.0 seconds later.
Create a quadratic function describing the height of the cannonball above the water with respect to time T. After how many seconds will the cannonball reach its maximum height?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Edward are manning a cannon that sits 50 feet above the water in a fortress tower.
They load, aim, and fire their cannon.
The cannon ball has an initial vertical velocity of 72 feet per second and hits the pirate ship ten feet above the water line exactly 5.0 seconds later.
:
Create a quadratic function describing the height of the cannonball above the water with respect to time T.
Force of gravity = -16t^2; initial height (t=0) = 50 ft; velocity = 72
therefore
H(T) = -16T^2 + 72T + 50
looks like this, green line indicates a height of 10' above the water
+graph%28+300%2C+200%2C+-4%2C+8%2C+-50%2C+200%2C+-16x%5E2%2B72x%2B50%2C+10%29+
:
After how many seconds will the cannonball reach its maximum height?
Max occurs on the axis of symmetry, find the axis of symmetry x=-b/(2a)
In this equation
T = %28-72%29%2F%282%2A-16%29
T = 2.25 seconds to reach max height