1. Inequalities 1_1.notebook March 13, 2013
Chapter 5
Graphing Inequalities and Systems of Equations
Today ­ 5.1
Thursday ­ 5.2 (pi day??)
Monday ­ 5.3
Thursday ­ Test
Mar 12­10:33 PM
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2. Inequalities 1_1.notebook March 13, 2013
5.1 Solving Quadratic Inequalities in One Variable
Illustrate ­4 ≤ x ≤ 1 on a number line
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
Illustrate ­3 < x < 4 on a number line
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
included
not included
Mar 12­10:56 PM
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3. Inequalities 1_1.notebook March 13, 2013
Quadratic inequalities in One Variable
can be written in general form 4 ways:
What is the solution to the inequality
x 2 ­3x + 2 > 0
First lets graph y = x 2 ­3x + 2
Mar 12­11:30 PM
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4. Inequalities 1_1.notebook March 13, 2013
x­intercepts of the graph of a quadratic function are called
critical values of the corresponding quadratic inequality.
These values are used to illustrate solutions to inequalities on
number lines
Example #1
Solve this inequality: 2x 2 ­ 7x > ­3
Represent the solution on a number line.
Mar 12­11:39 PM
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5. Inequalities 1_1.notebook March 13, 2013
Example #2
Solve : 5x ≥ 2(x 2
-6) (not using a number line)
Mar 13­12:02 AM
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6. Inequalities 1_1.notebook March 13, 2013
Example #3
The length of a rectangle is 2 cm greater than its width. The area of the
rectangle is at least 8 cm 2 . What are possible dimensions of the rectangle?
Mar 13­12:13 AM
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7. Inequalities 1_1.notebook March 13, 2013
Homework
Page 345 #1­6, 8a, 10, 11, 13, 14
Mar 13­12:13 AM
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