Transcript D23 Punkin Chunkin

College Algebra
Math 130
Amy Jones Lewis
Homework Review
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10x2 – 1 = 0
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-x2 + 8x = 2
Punkin’ Chunkin’
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Every year, the city of Millsboro, Delaware,
holds a competition called the World
Championship Punkin’ Chunkin’, which is a
pumpkin throwing competition. Participants
build a pumpkin catapult that hurls a pumpkin.
The catapult that hurls the pumpkin the
farthest is the winner.
Punkin’ Chunkin’
http://www.youtube.com/watch?v=559yuhpsd4Y&feature=r
elated
Punkin’ Chunkin’

You can model the motion of a pumpkin that is
released by a catapult by using the vertical
motion model y = -16t2 + vt + h, where
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t is the time that the object has been moving in
seconds
v is the initial velocity of the object in ft per sec.
h is the initial height of the object in feet
y is the height of the object in feet at time t
seconds.
Punkin’ Chunkin’

Suppose that a catapult is designed to hurl a
pumpkin from a height of 30 feet at an initial
velocity of 212 feet per second.
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Write a quadratic function that models the
height of the pumpkin in terms of time.
Punkin’ Chunkin’

Write an equation that you can use to
determine when the pumpkin will hit the
ground.
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Solve the equation.

Do both solutions have meaning in the
problem situation?
Punkin’ Chunkin’

What is the height of the pumpkin three
seconds after it is launched from the catapult?
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What is the height of the pumpkin eight
seconds after it is launched from the catapult?
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What is the height of the pumpkin 20 seconds
after it is launched from the catapult?
Punkin’ Chunkin’

When is the pumpkin at its highest point?
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What is the maximum height of the pumpkin?

When is the pumpkin at a height of 500 feet?

Is your answer confirmed by your graph?
Homework
Next Class: Wednesday, November 24