Approximating a Quadratic Regression by hand.

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Approximating a Quadratic Regression by hand.
Given a set of discrete data we want to determine
a quadratic equation model that approximates the
data as close as possible. The phrase quadratic
of best fit or quadratic regression is often used.
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The graph of given data is shown and you need to
determine the equation for this parabola.
The zeroes would be difficult to determine. Why?
Therefore we will use the vertex and a chosen
point (4,4).
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QUADRATIC REGRESSION BY HAND

• Example 1 Given the vertex and a point.
• Vertex (2,6) and Point (4,4)

• Substitute given info into
• Solve for a.
• Rewrite the equation
• using the a that you
• find and the vertex point.

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QUADRATIC REGRESSION BY HAND

• Example 2 Given the vertex and a point.
• Vertex (1,-4) and Point (0,-3)

• Substitute given info into
• Solve for a.
• Rewrite the equation
• using the a that you
• find and the vertex point.

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Example Approximate the path of the projectile
the Human Cannon Ball.
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QUADRATIC REGRESSION BY HAND

• Example 1 Given 2 zeroes and a point.
• Zeroes at -2 and 1, and Point (-1,-4)

• Substitute given info into
• Solve for a.
• Rewrite the equation
• using the a that you
• find and the given zeroes.

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QUADRATIC REGRESSION BY HAND

• Example 2 Given 2 zeroes and a point.
• Zeroes at -5 and 3 , and Point (-2,-45)

• Substitute given info into
• Solve for a.
• Rewrite the equation
• using the a that you
• find and the given zeroes.