1. Integers

2. Green counters = positive numbers = + 3
Red counters = negative numbers
= -3

3. 1 green counter and 1 red counter together – cancel each other outx x x x x x

4. Subtracting Integers

5. x x + 4 - + 2 +4 - +2 = +2 Subtracting Integers To subtract,
remove 2 green
+ 4 -
2 green (2 positive) remain
+ 2
= +2

6. x x x - 4 - - 3 -4 - -3 = -1 Subtracting Integers To subtract,
remove 3 red
- 4 -
1 red (1 negative) remains
- 3
= -1

7. x x x + 2 - + 3 +2 - +3 = -1 Subtracting Integers To subtract,
remove 3 green
+ 2
There aren’t enough green counters to subtract, so we will need to add one -
To add a green, we also need to add a red (we add 1 “zero pair”
+ 3
Now we can remove the final green
1 red (1 negative) remains
= -1

8. x x x - 2 - - 3 -2 - -3 = +1 Subtracting Integers To subtract,
remove 3 red
- 2
There aren’t enough red counters to subtract, so we will need to add one -
To add a red, we also need to add a green (we add 1 “zero pair”
- 3
Now we can remove the final red
1 green (1 positive remains
= +1

9. x x x - 2 - + 3 -2 - +3 = -5 Subtracting Integers To subtract,
remove 3 green
- 2
There aren’t any green counters to subtract, so we will need to add 3 x x x -
To add 3 greens, we also need to add 3 reds (we add 3 “zero pairs”
+ 3
Now we can remove 3 greens
5 red (5 negative) remain
= -5

10. x x + 3 - - 2 +3 - -2 = +5 Subtracting Integers To subtract,
remove 2 red
+ 3
There aren’t any red counters to subtract, so we will need to add 2 x x -
To add 2 red, we also need to add 2 green (we add 2 “zero pairs”
- 2
Now we can remove 2 red
5 green (5 positive) remain
= +5

11. Subtracting is adding the opposite
Subtracting Integers
Subtracting is adding the opposite
10 – 5 = 5 = 5 +

12. Now, follow the rules for addition:
Subtracting integers + =
Subtracting is adding
the opposite - - -3 + + 2 =
Now, follow the rules for addition:
Same signs, add and keep = -5

13. Now, follow the rules for addition:
Subtracting integers + =
Subtracting is adding
the opposite - - -4 + + 8 =
Now, follow the rules for addition:
Same signs, add and keep =
-12

14. Now, follow the rules for addition:
Subtracting integers + =
Subtracting is adding
the opposite - - -6 + + 9 =
Now, follow the rules for addition:
Same signs, add and keep =
-15

15. + + - - + + 7 = Subtracting integers 5 - 7 = +5 +5 + -7 = -2=
Subtracting is adding
the opposite +5 - - + + 7 =
Now, follow the rules for addition:
Different signs, subtract, keep the sign of the higher one = -2

16. + + - - + + 9 = Subtracting integers 6 - 9 = +6 +6 + -9 = -3=
Subtracting is adding
the opposite +6 - - + + 9 =
Now, follow the rules for addition:
Different signs, subtract, keep the sign of the higher one = -3

17. Now, follow the rules for addition:
Subtracting integers + - =
Subtracting is adding
the opposite +2 - - + + 9 =
Now, follow the rules for addition:
Same signs, add and keep =
+11

18. Now, follow the rules for addition:
Subtracting integers + - =
Subtracting is adding
the opposite +1 - - + + 6 =
Now, follow the rules for addition:
Same signs, add and keep = +7

19. Now, follow the rules for addition:
Subtracting integers + - =
Subtracting is adding
the opposite +5 - - + + 4 =
Now, follow the rules for addition:
Same signs, add and keep = +9

20. - - - - - + + 6 = Subtracting integers 3 - 6 = 3 -3 + +6 = +3=
Subtracting is adding
the opposite - 3 - - + + 6 =
Now, follow the rules for addition:
Different signs, subtract
Keep the sign of the higher one = +3

21. - - - - - + + 9 = Subtracting integers 2 - 9 = 2 -2 + +9 = +7=
Subtracting is adding
the opposite - 2 - - + + 9 =
Now, follow the rules for addition:
Different signs, subtract
Keep the sign of the higher one = +7

22. - - - - - + + 3 = Subtracting integers 7 - 3 = 7 -7 + +3 = -4=
Subtracting is adding
the opposite - 7 - - + + 3 =
Now, follow the rules for addition:
Different signs, subtract
Keep the sign of the higher one = -4

23. - - - - - + + 1 = Subtracting integers 10 - 1 = 10 -10 + +1 = -9=
Subtracting is adding
the opposite 10 - - - + + 1 =
Now, follow the rules for addition:
Different signs, subtract
Keep the sign of the higher one = -9

24. Rule: KEEP, SWITCH, CHANGE
Keep the sign of the first number, switch the subtraction sign to addition and change the sign of the second number