1. Chapter 2-1 Integers and Absolute Values

2. Here is a number line. +1 +2 +3 +4 +5 -5 -4 -3 -2 -1

3. An integer is any number on a number line.

4. -5 -4 -3 -2 -1 +1 +2 +3 +4 +5
Positive integers are integers greater than 0. They can be written without + sign.

5. Negative integers are integers less than 0. They are written with a-5 -4 -3 -2 -1 +1 +2 +3 +4 +5
Negative integers are integers less than 0. They are written with a
- sign.

6. Zero is neither negative nor positive.-5 -4 -3 -2 -1 +1 +2 +3 +4 +5
Zero is neither negative nor positive.

7. So, basically, any number I can imagine is an integer. Like 3. -3. 150
So, basically, any number I can imagine is an integer? Like 3? -3? 150? -150? 350 million billion gazillion?????
If it’s on the number line, it is an integer.

8. Here are some real-world examples…

9. Let’s write an integer for each situation.
Weather: 5 degrees below
Because this weather is below normal, the integer is written as -5.

10. Let’s write an integer for each situation.
Rainfall: 5 inches above normal
Because this rainfall is above normal, the integer is written as +5 or just 5.

11. Let’s write an integer for each situation.
Banking: a deposit of $23
Because deposit is adding an amount to your bank account, it is +23 or just 23.

12. You can also graph integers on a number line.

13. . . . . (-4, -2, 0, 5) Graph this set on a number line.-5 -4 -3 -2 -1 +1 +2 +3 +4 +5
Just draw a point (or a dot) on the location of the integer. That’s all!

14. . . . (-5, -1, 3) You get the point, right? Pun totally intended.
Graph this set on a number line.
(-5, -1, 3) . . . -5 -4 -3 -2 -1 +1 +2 +3 +4 +5
You get the point, right? Pun totally intended.

15. Hey, have you noticed that -5 and 5 are each 5 units (spaces) from 0?

16. +1 +2 +3 +4 +5 -5 -4 -3 -2 -1
-5 and 5 are both 5 spaces away from 0. They have the same absolute value.

17. Absolute value of a number is the distance between the number and 0 on a number line.

18. And it’s written like this…

19. 5 units
5 units +1 +2 +3 +4 +5 -5 -4 -3 -2 -1
5 = 5
-5 = 5

20. -5 = 5
5 = 5
This means that the absolute value of both -5 and 5 are 5 (distance from 0).

21. Let’s try this one…
-4 = 4
4 units +1 +2 +3 +4 +5 -5 -4 -3 -2 -1

22. So…basically…

23. -560
560 =
2010 =
-256,487 =
256,487
OK…I get it, I get it!

24. Now, you can even do this…

25. 12 + 4
-12 + 4 = = 16 -5 - -1 5 - 1 = = 4 2 + -3 2 + 3 = = 5 -7 - 5 7 - 5 = 2 =

26. Good job!