2. 1.2 Introduction to Signed Numbers
Chapter 1 Introduction to Algebra: Integers

3. 1.2 Introduction to Signed Numbers
Objectives
Write positive and negative numbers used in everyday situations.
Graph signed numbers on a number line.
Use the < and > symbols to compare integers.
Find the absolute value of integers.
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4. Numbers greater than zero are called positive numbers.
Objective 1: Write positive and negative numbers used in everyday situations.
Numbers greater than zero are called positive numbers.
Numbers less than zero are called negative numbers.
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5. Objective 1: Write positive and negative numbers used in everyday situations.
Copyright © 2010 Pearson Education, Inc. All rights reserved.

6. Objective 1: Write positive and negative numbers used in everyday situations.
Copyright © 2010 Pearson Education, Inc. All rights reserved.

7. Objective 1: Write positive and negative numbers used in everyday situations.
Copyright © 2010 Pearson Education, Inc. All rights reserved.

8. Example Write “a loss of $500” as a number with its appropriate sign.
Objective 1: Write positive and negative numbers used in everyday situations.
Example Write “a loss of $500” as a number with its appropriate sign.
– $500
Raised negative sign
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9. Objective 2: Graph signed numbers on a number line.
A number line is like a thermometer turned sideways.
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10. Objective 2: Graph signed numbers on a number line.
Graph each number on the number line.
(a) –5 (b) 3 (c) 1 ½ (d) 0 (e) –1
Example
(a)
(e)
(d)
(c)
(b)
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11. Objective 3: Use the < and > symbols to compare integers.
Integers are the numbers
…, –5, –4, –3, –2, –1, 0, 1, 2, 3 ,4, 5,…
“>” means greater than
“<“ means less than
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12. Objective 3: Use the < and > symbols to compare integers.
Copyright © 2010 Pearson Education, Inc. All rights reserved.

13. Objective 3: Use the < and > symbols to compare integers.
Copyright © 2010 Pearson Education, Inc. All rights reserved.

14. Objective 3: Use the < and > symbols to compare integers.
Write < or > between each pair of numbers to make a true statement.
0 ____ 2
1 ____–4
–4 ____–2
Example
0 < 2
1 > –4
–4 < –2
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15. Objective 4: Find the absolute value of integers.
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16. Objective 4: Find the absolute value of integers.
Find each absolute value.
|4|
|–4|
Example
4 spaces, so |4| = 4
4 spaces, so |–4| = 4
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