This document discusses subtracting positive and negative numbers. It provides examples of subtracting numbers with opposite signs and the same signs. It explains that subtracting a number is the same as adding its opposite. The rules for subtracting signed numbers are to change subtraction to addition of opposites, and follow the rules for adding signed numbers by considering the signs and absolute values. Examples are given to illustrate the rules. The document concludes with assigning written and mixed practice exercises on pages 87-88 involving subtracting positive and negative numbers.

1. 3.4 Subtraction
(positive and negative numbers)

2. Example
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3. Example
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4. Opposites
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5. Without the Number Line
1. Change subtracting to adding the opposite
2. Follow the rules for adding signed numbers
 If the two numbers have opposite signs
1. Subtract the absolute values
2. Use the sign of the “bigger” number
 If the two numbers have the same signs
1. Add the absolute values
2. Keep the sign the same

6. Example
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7. Example
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8. Example
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9. Example
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10. Assignment
 Page 87
 Written Exercises #1, 2, 7 – 40 odd
 Page 88
 Mixed Practice Exercises # 1 – 32 odd