9'4 Graphing Quadratic Functions

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9.4 Graphing Quadratic Functions

• Goal Identify critical features of a parabola

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Objective - To algebraically find critical
features of parabolic curves.
Quadratic Equation
Quadratic Term
Linear Term
Constant Term
a
opens up
y-intercept
-a
opens down
c
shifts up
-c
shifts down
skinny parabola
wide parabola
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Evaluate the following if x -3.
1)
3)
2)
4)
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Finding Critical Features of Quadratics
x
y
Axis of Symmetry
-3 -2 -1 0 1 2 3
29
x 3
18
9
2
-3
-6
Vertex
(3,-7)
-7
-6
4 5
-3
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Finding Critical Features of Quadratics
Vertex
Axis of Symmetry
Opens Up/Down
Opens Up
Y-intercept
(0, 2)
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Now, Graph the quadratic.
Vertex
Opens Up/Down
Opens Down
Y-intercept
(0, 2)
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Find the critical features of the quadratic below.
Vertex
Axis of Symmetry
Opens Up/Down
Opens Down
Y-intercept
(0, 0)
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Find the critical features of the quadratic below.
Vertex
Axis of Symmetry
Opens Up/Down
Opens Up
Y-intercept
(0, 4)