Graphing Quadratic Functions General Form

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Graphing Quadratic Functions General Form

• It is assumed that you have already viewed the
  previous three slide shows titled
• Graphing Quadratic Functions Concept
• Graphing Quadratic Functions Standard Form
• Graphing Quadratic Functions Converting
  General Form To Standard Form

• The next three pages are summaries from those
  shows, and are important to understanding this
  module.

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General Form of a Quadratic Function
Standard Form of a Quadratic Function
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Sketch the Graph of a Quadratic in Standard Form
x-int f (x) 0 and solve for x
y-int x 0 and solve for y
Draw the parabola
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Vertex - General Form

• Given the general form of a quadratic function

the x-value of the vertex is given by
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• There are two other helpful concepts for
  graphing a quadratic function that is in general
  form.

• Concept 1

We already know that the x-value of the vertex is
given by
To find the y-value of the vertex, just plug the
x-value into the function
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Thus, the vertex of the graph of the quadratic
function in general form is given by

• Concept 2

The a of the general form is the same value as
the a in the standard form.
This means that the a in the general form can be
used to determine the face up/face down behavior,
just as it did in the standard form.
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Summary for Graphing Quadratics in General Form
x-int f (x) 0 and solve for x
y-int x 0 and solve for y
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• Example

Sketch the graph of the given quadratic function.
Face down
Vertex
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(No Transcript)
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Axis of Symmetry x x-value of vertex
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x-intercepts
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y-intercept
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Summary
Face down
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Draw the branch of the parabola on the right side
of the axis.
Use symmetry to draw the left branch.
Label
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END OF PRESENTATION
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