1. Operations with Integers
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2. What are Integers?
• Integers include all of the positive and
negative whole numbers, and zero.
Integers NOT Integers
3 -1.652
-4 ¾
12 2.5
0 0.7

3. Adding Integers
• On a number line:
1. Find the first number.
2. Move the distance of the second number.
a) Positive (+) numbers, move RIGHT
b) Negative (-) numbers, move LEFT
3. Where you land is the answer!
Example: 5 + 8

4. Examples:
• -4 + 1 =
• 7 + -9 =
• -8 + -4 =

5. Adding Integers Rules
• Use if you don’t have a number line.
• When the integers are:
▫ Both Positive: add the numbers
 Ex: 4 + 6 =
▫ Both Negative: add the numbers and
make it negative
 Ex: -2 + -5 =
▫ One Positive and One Negative: Subtract
and use the sign of the bigger number.
 Ex: -7 + 4 =

6. You Try!
• Add the integers.
• 12 + -4 =
• -8 + -9 =
• 2 + 13 =
• -11 + 5 =

7. Subtracting Integers
• Change the minus to a plus, and change the
sign of the number you are subtracting.
• Ex: -14 – 6 =
• Subtracting a Negative is the same as Adding!
• Ex: 12 – (-3) =

8. You Try!
• Subtract the integers.
• 17 – 4 =
• -8 – (-5) =
• 2 – 11 =
• -4 – 12 =