Notes – Addition and Subtraction of Integers (with counting chips)

We are learning to…add and subtract positive and negative integers with counting chips.

Wednesday, April 19, 2023

Counting Chips

Take only the small red and blue Algebra Tiles out of the bag. Please put all other tiles back into the bag.

Divide your tiles so that everyone in your group has an equal amount of tiles.

Rules for Counting Chips

Today we will be modeling the addition and subtraction of integers with counting tile manipulatives.

Rules:1. When groups of different colored chips

are put together a red and a blue chip cancel each other out.

2. When groups of the same colored chips are put together nothing cancels out.

PracticeDON’T FORGET TO LABEL YOUR ANSWERS WITH THE CORRECT COLOR OF CHIPS

1. 3 reds + 4 reds = ________ 2. 5 blues + 6 blues = ________

3. 2 blues + 8 reds = ________ 4. 8 reds + 4 reds = ________

5. 9 blues + 6 reds = ________ 6. 7 blues + 1 blue = ________

7 Reds 11 Blues

6 Reds 12 Reds

3 Blues 8 Blues

Fix the common mistake!

Gordon was trying to add 13 blue chips to 15 red chips and he thinks that the solution is 28. Explain to Gordon what he did incorrectly. Help him fix his thinking so he won’t answer future problems incorrectly. Explain in complete pictures and draw

pictures to help Gordon!

Addition of Integers The Red Tiles represents…one negative(-1).

The Blue Tiles represents…one positive (+1).

More Practice DON’T FORGET TO LABEL YOUR ANSWERS WITH THE CORRECT SIGN

8 2 _______ 4 ( 3) _______ 5 ( 9) _______

7 ( 2) _______ 9 6 _______ 10 ( 10) _______

-6 -7 -14

5 -3 0

Try the rest of the practice with your group!

Hints of adding integers… If you are adding integers with the SAME

sign…just add like normal and keep the sign.

If you are adding integers with DIFFERENT signs ask yourself 2 questions… 1. Are there more positives or negatives? This

will tell you the sign of your solution. 2. How many more do I have? This will tell you

the value of your solution.

Subtraction of Integers

Wednesday, April 19, 2023

We are learning to…add and subtract positive and negative integers with counting chips.

Subtracting Integers with Counting Chips

Subtraction means …to take away, so to show this with chips we will have to…start with a certain amount of chips and then take away from that group.

9 5 _______ 8 ( 3) _______ 7 ( 6) _______ 4 -5 -1

Now try:

4 ( 2) _______ PROBLEM ?

14 ( 8) _______ 9 ( 9) _______ 15 ( 8) _______ -6 0 -7

How can we take a negative away from a positive? Solution:

Add in “Zero Pairs” until you have enough negative (or positives) to take away!

A Zero Pair is a positive and a negative chip. Since the two chips cancel each other, you are really

adding in zero and not changing the problem. Remember:

+ = 0

4 ( 2) _______ 6

Subtraction of Integers Practice

5 ( 4) _______ 7 ( 2) _______ 8 3 _______

9 5 _______ 2 10 _______ 1 ( 4) _______

9 -11 9

-14 -8 3

Now try a few assessment questions to test your skills adding and

subtraction integers!