This document provides an introduction to adding and subtracting integers. It defines integers as whole numbers and their opposites. When adding integers with the same sign, you add them together and keep the sign. When adding integers with different signs, you find the difference and keep the sign of the higher number. Subtraction can be thought of as "adding the opposite". The "-" symbol has three meanings: subtraction, negative number, and change of direction.

1. 1
Adding Integers
Pre-Algebra
Unit 2 Lesson 3

2. 2
What is an integer?
Integers: All whole numbers and its opposite
-45
1.25
100
2/5
-12.

3. 3
Adding
+ =apple apple MORE apples
+ =fart fart Dangerous Gasses!
(MORE farts)

4. 4
Adding Integers with the same sign:
Rule: Same sign, add all together, keep sign.
Try these problems with the chips:
2 + 7 =
-3 + -3 =
-5 + -1 =
6 + 4 =

5. 5
Adding Integers with the same sign:
Write out these problems on paper using + and - symbols:
-3 + (-4) = -8 + (-2) = 3 + 7 =
example

6. 6
Adding Integers with different signs:
Rule: Different sign, find difference, take sign
of higher number.
-3 + 9 8 + (-10)
Try these problems with the chips:
5 + (-2) =
-6 + 4 =
(-10) + 10 =

7. 7
Adding Integers with different signs:
Right out these problems on paper using + and - symbols:
7 + (-8) = -4 + 10 = 3 + (-6) =
SMOTD
example

8. 8
Absolute Value: Distance from that number to zero
-1 0-2-3-4-5 1 2 3 4 5
-5 + |-10|

9. 9
Integer Jan Ken Po
(rock paper scissors)

10. 10

11. 11
Subtracting Integers
Unit 2 Lesson 4

12. 12

13. 13
Subtraction = "adding the opposite"
6 - 4 can be seen as... 6 + (-4)
5 - 10 can be seen as... 5 + (-10)
-2 - 7 can be seen as...
-9 - 3 can be seen as...

14. 14
The "-" symbol has three meanings, what are
they?
-
-
-

15. 15
8 - (-7) can be seen as...
-15 - -2 can be seen as...
-4 - - 4 can be seen as...
Do these problems:
5 - - 10
-3 - 8
-7 - - 6