Solving Quadratics EQ: How do we determine solutions of and graph quadratic inequalities?

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Solving Quadratics EQ How do we determine
solutions of and graph quadratic inequalities?
M2 Unit 1C Day 6
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Lets review graphing linear inequalities
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Boundary lines
If the inequality is or , the boundary line
is solid its points are solutions.
Example The boundary line of the solution set of
y 3x - 2 is solid.
If the inequality is lt or gt, the boundary line
is dotted its points are not solutions.
Example The boundary line of the solution set of
y lt - x 2 is dotted.
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Determine if the point is a solution to the
quadratic inequality
3 lt -11
(2, 3) is NOT a solution!
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Determine if the point is a solution to the
quadratic inequality
(0,-2) is a solution!
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Quadratic Inequalities
Dashed parabola Shade below vertex
Solid parabola Shade below vertex
Dashed parabola Shade above vertex
Solid parabola Shade above vertex
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Steps to graph quadratic inequalities

• Determine if dashed or solid
• Graph parabola
• Shade above or below the parabola (vertex)

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Graph the quadratic using the axis of symmetry
and vertex.
Vertex
Y-intercept
One more point
Since the parabola is solid!
Since shade above!
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Graph the quadratic using the axis of symmetry
and vertex.
Vertex
Y-intercept
One more point
Since lt the parabola is dashed!
Since lt shade below!
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Graph the quadratic using the axis of symmetry
and vertex.
Vertex
Y-intercept
One more point
Since lt the parabola is dashed!
Since lt shade below!
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Graph the quadratic using the axis of symmetry
and vertex.
Vertex
Y-intercept
One more point
Since the parabola is solid!
Since shade below!
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Assignment Pg 98 (1-10 all, 12-18 even)
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