1. ADDING & SUBTRACTING INTEGERS by Angela Gallacher NS 1.2 and AF 1.3

2. Integers
Whole numbers and their opposites are integers such as 6 and -6.
Zero is also a whole number. -6 6
Opposites

3. Negative Numbers Are Used to Measure Temperature

4. Negative Numbers Are Used to Measure Under Sea Level30 20 10
-10
-20
-30
-40
-50

5. Negative Numbers Are Used to Show Debt
Let’s say your parents bought a car but had to get a loan from the bank for $15,000.When counting all their money they add in
-$ to show they still owe the bank.

6. INTRODUCTION TO INTEGERS
We can represent integers using red and yellow counters.
Red tiles will represent negative integers, and yellow tiles will represent positive integers.
Negative integer
Positive integer

7. INTRODUCTION TO INTEGERS
The diagrams below show 2 ways to represent -3.
Represent -3 in 2 more ways. -3 -3

8. INTRODUCTION TO INTEGERS
You may represent -3 by using 3 red tiles and any number of groups of +1 and -1 tiles

9. INTRODUCTION TO INTEGERS
Tell which integer each group of tiles represents. +1 -2 +2

10. INTRODUCTION TO INTEGERS
Tell which integer each group of tiles represents. -1 -4 +4

11. INTRODUCTION TO INTEGERS
Tell which integer each group of tiles represents. +5 -4 -3

12. INTRODUCTION TO INTEGERS
If there are the same number of red tiles as yellow tiles, what number is represented?
It represents 0.

13. Zero Pairs -3 + 4 = 6 – 10 = Zero Bank -6 + -7 = 12 + -7 = -3 – (-4) =
5 – (-9) =
Zero Bank
To use zero bank get out of slide show!

14. On your own -4 + 4 = -6 – 15 = Zero Bank -6 + 13 = 2 + -13 =
-4 – (-4) =
-9 – (-9) =
Zero Bank