1. Positive and Negative Numbers
Understanding Integers
Positive and Negative Numbers

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

3. Zero (0) is neither positive nor negative.
Definition
Negative number – a number less than zero. -6 -5 -4 -3 -2 -1 1 2 3 4 5 6
Zero (0) is neither positive nor negative.

4. Definition
Integers – all whole numbers and their opposites.

5. Definition
Opposite Numbers – numbers that are the same distance from zero in the opposite direction. The sum of two opposites is 0. -6 -5 -4 -3 -2 -1 1 2 3 4 5 6

6. Opposite Integers 7
opposite -7 5 -5
opposite

7. Key Words Positive Numbers Negative Numbers Loss Less Decrease Drop
Gain
Increased
Above Up
More
Rose
Negative Numbers
Loss
Less
Decrease
Drop
Below
Down

8. Integers Are Used to Measure Temperature

9. Integers Are Used to Measure Above and Under Sea Level30 20 10
-10
-20
-30
-40
-50

10. Integers Are Used to Show Money
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.

11. Write an integer to represent each situation.
The temperature dropped 12 degrees.
Sam’s bank account increased by $ 25.
The Arizona Cardinals lost by 3 points.
Jade has $55. She earns $27, spends $23, then spends $8. How many dollars does she have or owe?
-12
+25 -3
+$51.00

12. The highest elevation in North America is Mt
The highest elevation in North America is Mt. McKinley, which is 20,320 feet above sea level. The lowest elevation is Death Valley, which is 282 feet below sea level. What is the distance from the top of Mt. McKinley to the bottom of Death Valley?

13. 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.

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

15. Integer Addition Rules
Rule #1 – If the signs are the same, pretend the signs aren’t there. Add the numbers and then put the sign of the addends in front of your answer.
9 + 5 = 14
= -14

16. Solve the Problems =
4 + 7 =
(+3) + (+4) = =
5 + 9 = = -8 11 7
-13 14
-18

17. Integer Addition Rules
Rule #2 – If the signs are different pretend the signs aren’t there. Subtract the smaller from the larger one and put the sign of the larger one in front of your answer. =
Larger number
Answer = - 4
9 - 5 = 4

18. 3 + -5 = -4 + 7 = (+3) + (-4) = -6 + 7 = 5 + -9 = -9 + 9 =
Solve These Problems -2 = =
(+3) + (-4) = = = =
5 – 3 = 2 3
7 – 4 = 3
4 – 3 = 1 -1 1
7 – 6 = 1
9 – 5 = 4 -4
9 – 9 = 0

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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