Investigating Graphs of Quadratic Functions

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Investigating Graphs of Quadratic Functions
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Objectives

• You will be able to describe how the values of
  the coefficients of a quadratic function affect
  the graph.
• You will be able recognize the graph of a
  quadratic function by its equation.

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Review

• How to graph a quadratic function by hand
• 1. Find the x-coordinate of the vertex -b/(2a).
• 2. Make a table of values, using x-values to the
  left and right of the vertex.
• 3. Plot the points and connect them with a
  smooth curve to form a parabola.

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• Example

a 1 b -2 c -3
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Pick values to left and right of Vertex
(equidistant from vertex)
-The vertex is located at (1,-4).
-One unit to the right and left of x1 are x0
and x2.
-Two units to the right and left of x1 are x3
and x-1.
-Make a table by substituting these x-values into
your function to find their corresponding
y-values.
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Table of Values
Point X Y
Vertex 1 -4
B 2 -3
C 0 -3
D -1 0
E 3 0
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Plot the Points and Connect a Smooth Curve
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Investigation

• Open your laptop
• Open the file on your desktop labeled
  Multimedia1a_Dynamic_Worksheet_EHP.html
• Answer the questions on the worksheet by
  investigating using the sliders