Adding Integers

Adding Integers

by Mr. Lemoi

​3 Situations

​There are 3 different situations you might see when adding integers

​

​1.) Positive + Positive

​2.) Negative + Negative

​3.) Positive + Negative

​Positive + Positive

​This is the basic one.

​

​This is like 4 + 5 = 9

​

​You have 4 Good Guys and you get 5 MORE Good Guys to join your Good Guy Army.

​

​You just add them up and now you have 9 Good Guys.

Multiple Choice

1 + 8

• 9

• 8

• 7

• 6

​Negative + Negative

​This is JUST LIKE positive + positive, but your answer will be negative.

​

​-4 + (-5) = -9

​

​I have 4 BAD guys and 5 more BAD guys so now I have 9 BAD guys

Multiple Choice

-10 + (-4)

• 6

• -6

• -14

• 14

Multiple Choice

-3 + (-5)

• -8

• -2

• 9

• 15

​Negative + Negative

​You might see this type of question written a few different ways

​

​-2 + (-4) = -6​

​or

​-2 + -4 = -6

​or

​-2 -4 = -6

​

​Don't be scared. It's all the same.

Multiple Choice

-5 - 3

• 2

• 8

• -8

• -2

Multiple Choice

-1 - 6

• -7

• -5

• -6

• -8

​Positive + Negative

​This is where it gets harder. If you have SOME positives and SOME negatives you need to figure out which you have more of.

​

​50 + (-60) = More negatives so answer will be negative

​

​-4 + 50 = More positives so answer will be positive

Multiple Choice

Will your answer be positive or negative?

274 - 899

• Positive

• Negative

Multiple Choice

Will your answer be positive or negative:

-58 + 99

• Positive

• Negative

​Positive + Negative

​Once you know whether your final answer is positive or negative, then you must subtract the number with the highest absolute value minus the number with the smaller absolute value.

​

​-50 + 20 = Answer will be negative

​​50 - 20 = 30

​

​Final answer = -30

​Positive + Negative

​If it helps you to think of a Good Guy vs Bad Guy battle then do it.

​

​-50 = 50 bad guys

​+20 = 20 good guys

​

​Bad guys will win. They will have 30 bad guys left over

​

​-50 + 20 = -30

Multiple Choice

-2 + 6

• 4

• 8

• -6

• -2

Multiple Choice

4 + (-5)

• -1

• 1

• 9

• -9

Multiple Choice

21 + (-24)

• -5

• 45

• -3

• 15

Multiple Choice

-42 + 42

• -42

• 0

• 84

• -84

Multiple Choice

11 + (-8)

• 6

• -5

• 3

• -19