SOLUTION: A soccer ball is kicked from the goal crease. The ball travels along the path modelled by the equation {{{h=-.05d^2+3d}}}, where h is the height of the ball in meters and d is the

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Question 1032520: A soccer ball is kicked from the goal crease. The ball travels along the path modelled by the equation h=-.05d%5E2%2B3d, where h is the height of the ball in meters and d is the horizontal distance in meters.
a) How far does the ball travel horizontally?
My answer: 0.5d%5E2
d = 6
The ball travels 6m before returning to the ground
b) If a 1.85 m tall soccer player stands 40 m away from the goalkeeper, how far over his head will the ball travel?
c) What is the maximum height the ball will travel to?
Thanks

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A soccer ball is kicked from the goal crease. The ball travels along the path modelled by the equation h=-.05d^2+3d, where h is the height of the ball in meters and d is the horizontal distance in meters.
a) How far does the ball travel horizontally?
The height is zero when the ball hits the ground.
Solve
-0.05d^2 + 3d = 0
Factor:
-d(0.05d - 3) = 0
0.05d - 3 = 0
0.05d = 3
d = 300/5 = 60 meters
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b) If a 1.85m tall soccer player stands 40m away from the goalkeeper, how far over his head will the ball travel?
Question:: From what point was the ball kicked?
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c) What is the maximum height the ball will travel to?
Max occurs when d = -b/(2a) = -3/(2*0.05) = 30
h(30) = -0.05(30)^3 + 3(30) = -45+90 = 45 ft (maximum height)
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Cheers,
Stan H.
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