Positive and Negative Numbers

1. Positive and Negative Numbers by Monica Yuskaitis

2. Definition • Positive number – a number greater than zero. 0 1 2 3 4 5 6

3. Definition • Negative number – a number less than zero. 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6

4. Definition • Opposite Numbers – numbers that are the same distance from zero in the opposite direction 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6

5. Definition • Integers – Integers are all the whole numbers and all of their opposites on the negative number line including zero. 7 opposite -7

6. Negative Numbers Are Used to Measure Temperature

7. Negative Numbers Are Used to Measure Under Sea Level 0 10 20 30 -10 -20 -30 -40 -50

8. 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 $5,000. When counting all their money they add in -$5.000 to show they still owe the bank.

9. Positive & Negative Numbers Working with positive and negative numbers is like driving in traffic. You have to watch the traffic signs and follow the driving rules.

10. Hint • If you don’t see a negative or positive sign in front of a number it is positive. 9 +

11. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 When the number is positive count to the right. When the number is negative count to the left. + -

12. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 + - +3 + -5 = -2

13. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 + - +6 + -4 = +2

14. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 + - +3 + -7 = -4

15. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - + -3 + +7 = +4

16. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - + -5 + +3 = +4

17. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - + -2 + +8 = +6

18. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - + -5 + +2 = -3

19. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - - -4 + -2 = -6

20. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - - -2 + -3 = -5

21. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - - -1 + -4 = -5

22. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 - - -4 + -1 = -5

23. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 + + 4 + 1 = 5

24. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 + + 3 + 2 = 5

25. One Way to Add Integers Is With a Number Line 0 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 + + 1 + 5 = 6

26. Solve the Problems below using a number line. -3 + -5 = 4 + 7 = 3 + - 4 = - 8 -1 11 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12

27. Solve the Problems below using a number line. -6 + -7 = 5 + 9 = -9 + -3 = -12 14 -13 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14

28. Integer Addition Rules • Rule #1 – If the signs are the same, add the numbers and keep the original sign. 9 + 5 = 14 -9 + -5 = -14

29. Integer Addition Rules • Rule #2 – If the signs are different, subtract and put the sign of the farthest from zero on the number line. -9 + 5 = 9 - 5 = 4 Larger number Answer = - 4

30. Solve These Problems • 3 + -5 = • -4 + 7 = • 3 + (-4) = • -6 + 7 = • 5 + -9 = • -9 + 9 = - 2 5 – 3 = 2 0 -4 1 -1 3 9 – 9 = 0 9 – 5 = 4 7 – 6 = 1 4 – 3 = 1 7 – 4 = 3