1. Positive and Negative Numbers

2. What is…

3. … a positive number?
A number that is greater than zero

4. … a negative number?
A number that is less than zero.

5. …an opposite number?
Numbers that are the same distance from zero in the opposite direction.

6. …an integer?
All whole numbers and their opposites on a number line
9 opposite -9

7. This is a number line
negative
positive

8. Using positive and negative numbers…
Is like driving in traffic. You have to watch for the signs!

9. This is the positive sign!

10. This is the negative sign!

11. Hint:
If you don’t see a sign in front of a number, don’t panic! No sign means it is a positive number!

12. What do we already know?
Positive integers are on the right side of zero
Negative integers are on the left side of zero
This means that they are opposites = 0
Connect to Learning Objective
Show me a positive number on the white board.
Negative number.
Write two integers that are opposite that equal to zero.
Tell your partner why is the sum of the two integers zero.
Negative
Positive

13. Comparing Integers
Use the number line to compare the following integers with >, <, or =. -4 -2 1 -3 -5
<
<
>
Hint: On a number line, the number to the left is always less than the number to the right.

14. Comparing Integers
Use the number line to compare the following integers with >, <, or =. -3 -5 -1
>
>
>
Hint: On a number line, the number on the top is always greater than the number on the bottom.

15. Ordering Integers
Use the number line to put the following integers in order from least to greatest.
-4, 3, 0, and -5
-5, -4, 0, 3

16. Now, you’re probably saying, “That’s interesting and everything, BUT where are negative numbers in the real world?? ??

17. Negative Numbers Are Used to Measure Temperature

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

19. Positive and negative numbers are used when keeping track of money.
$$ you earn
- Negative -
$$ you spend

20. Write an integer to describe the real world situation:
Gain 3 pounds:
Withdraw $15:
5 feet below sea level:
Move ahead 4 spaces:
-15 -5
4 or +4

21. Positive Numbers are Used to Show Earnings or Assets
When you get paid (or win the lottery), you add that $$ to your account.

22. Negative Numbers are Used to Show What You Owe or Debt
If your mom loaned you $10 for pizza,
Mom,
I. O. U.
$10
The $10 you owe her is described by the integer -10.

23. Step 1: Plot the first integer on the number line.
You know how to plot an expression on the number line and find the sum. = 3
Step 1: Plot the first integer on the number line.
Step 2: Plot the second integer on the number line beginning where the last number left off. -2
RAJ
What is an integer?
Pair share
Pull sticks
Which example is positive integer? Choice A -4
Choice B 9
Tell your partner how do you know which one is a positive integer?
Use a sentence frame 的 knew that _ is a positive integer because_�
Repeat for negative integer. 5

24. You know how to plot an expression on the number line and find the difference.
5 + -2= 3
Step 1: Plot the first integer on the number line.
Step 2: Plot the second integer on the number line beginning where the last number left off. -2 5

25. You know how to plot an expression on the number line and find each sum.
Step 1: Plot the first integer on the number line.
Step 2: Plot the second integer on the number line beginning where the last number left off. =
- 4 -1 -3

26. Addition Rule 1
Rule #1 – If the signs are the SAME, ADD the numbers and then KEEP the sign of the addends.
(+) + (+) = (+)
(-) + (-) = (-)
EXAMPLE:
5 + 1 = 6
= -7

27. Addition Rule 2 -5 + 3 = -2 EXAMPLE:
Rule #2 – If the signs of the addends are DIFFERENT, SUBTRACT and keep the SIGN of the larger number
EXAMPLE:
= -2

28. Solve the Problems -3 + -5 = -8 4 + 6 = +3 + (+4) = 10 -6 + -7 =
5 + 9 = = -8 10 7
-13 14
-18

29. Adding Integers Using a Number Line * adding a positive integer *
ex. (-6) + 5 = -1
Start here at -6 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 +
then count forward or right 5 spaces

30. Solve the Problems
8 + 6 =
(-9) + 5 =
(–11) + 11 =
(–8) + 16 = 14 -4 8

32. Integer Subtraction Rule
Subtracting a negative number is the same as adding a positive. Change the signs and add.
ex. -1 – (-2) is the same as
-1 + (+2) and = 1
KEEP
CHANGE
CHANGE