Question 1073265
JP launches a rocket straight upwards from a height of 20 feet above the ground with an initial upward velocity of 85 feet per second. The equation h(t) = -16tē + 85t + 20 models the height of the rocket off of the ground, t seconds after the rocket is launched. 

a) Find the height of the rocket 3 seconds after it is launched. 
b) At what time will the rocket reach the maximum height?
Max height is the vertex of the parabola, at t = -b/2a
t = -85/-32 = 85/32 seconds.
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 What is the maximum height of the rocket? (4 pts)
Sub 85/32 in the equation.
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c) When will the rocket reach a height of 100 feet?
h(t) = -16tē + 85t + 20 = 100
Solve for t
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d) At what time will the rocket hit the ground?
h(t) = -16tē + 85t + 20 = 0
Solve for t