Notation and Modeling Addition of Integers
Learning Outcomes
- Model addition of integers with color counters
![This figure has a blue circle labeled positive and a red circle labeled negative.](https://s3-us-west-2.amazonaws.com/courses-images/wp-content/uploads/sites/277/2017/04/24220151/CNX_BMath_Figure_03_02_024_img.png)
![This figure has a blue circle over a red circle. Beside them is the statement 1 plus negative 1 equals 0.](https://s3-us-west-2.amazonaws.com/courses-images/wp-content/uploads/sites/277/2017/04/24220152/CNX_BMath_Figure_03_02_001.png)
example
Model: . Solution:Interpret the expression. | means the sum of and . |
Model the first number. Start with positives. | ![]() |
Model the second number. Add positives. | ![]() |
Count the total number of counters. | ![]() |
The sum of and is . |
try it
Model the expression.Answer:
Answer:
example
Model: .Answer: Solution:
Interpret the expression. | means the sum of and . |
Model the first number. Start with negatives. | ![]() |
Model the second number. Add negatives. | ![]() |
Count the total number of counters. | ![]() |
The sum of and is . |
try it
Model the expression.Answer:
Answer:
example
Model: .Answer: Solution:
Interpret the expression. | means the sum of and . |
Model the first number. Start with negatives. | ![]() |
Model the second number. Add positives. | ![]() |
Remove any neutral pairs. | ![]() |
Count the result. | ![]() |
The sum of and is . |
try it
Model the expression, and then simplify:Answer:
Answer:
example
Model: .Answer: Solution:
Interpret the expression. | means the sum of and . |
Model the first number. Start with positives. | ![]() |
Model the second number. Add negatives. | ![]() |
Remove any neutral pairs. | ![]() |
Count the result. | ![]() |
The sum of and is . |
try it
Model the expression, and then simplify:Answer:
Answer:
example
Model each addition.Answer: Solution
1. | |
Start with positives. | ![]() |
Add two positives. | ![]() |
How many do you have? | . |
2. | |
Start with negatives. | ![]() |
Add positives. | ![]() |
Remove neutral pairs. | ![]() |
How many are left? | ![]() |
. |
3. | |
Start with positives. | ![]() |
Add negatives. | ![]() |
Remove neutral pairs. | ![]() |
How many are left? | ![]() |
. |
4. | |
Start with negatives. | ![]() |
Add negatives. | ![]() |
How many do you have? | . |
try it
Model each addition. 1. 2. 3. 4.Answer:
1.
2.
3.
4.
Answer:
1.
2.
3.
4.