1. PART ONE -- NUMBER LINES
Name: _______________________
Date: _______________________
Addition Modeling Lab
PURPOSE: To practice adding integers with both number lines and
algebra tiles.
PART ONE -- NUMBER LINES
Examples:
Use the below number lines to model the given addition problems:
4 + 3 = _____
7 + (-3) = _____
-6 + (-3) = _____
= _____
-2 + (-6)= _____

2. = _____
(-1) = _____
= _____
(-8) = _____
1 + (-5)= _____
= _____
-9 + (-1) = _____
= ______

3. PART TWO – Algebra Tiles
Example: = 19
ADDING “SAME” SIGNS:
Key:
= Positive
= Negative
Directions:
Draw tiles onto below mats in order to model given problems (you may use “+” signs for
positives and “-” signs for negatives:
Adding Two Positives:
1. Represent in the mat below Represent in the mat below.
2 + 5 = ______ = ______
Represent in the mat below Represent in the mat below.
9 + 0 = ______ = ______
What do you notice about all of your above answers?
6. In the space below, write a rule for adding two positive numbers.

4. Adding Two Negatives:
7. Represent in the mat below Represent in the mat below.
= ______ = ______
9. Represent in the mat below Represent in the mat below.
= ______ = ______
11. What do you notice about all of the above answers?
12. In the space below, write a rule for adding two negatives.
Write a rule that works for both adding two positives and adding two negatives.

5. The zero pairs are circled. We remove zero pairs!
Example: (-3) = 3
In your own words, define zero pair.
When adding a positive # and a negative #, will you always have zero pairs?
3. Represent in the mat to the right.
Circle the zero pair(s).
How many zero pairs are in the problem ? ____
What is the solution to ? ____
4. Represent 4 + (-1) in the mat to the right.
How many zero pairs are in the problem? ____
What is the solution to 4 + (-1 )? ____
5. Represent in the mat to the right.
What is the solution to ? ____
ADDING “DIFFERENT” SIGNS:
Key:
= Positive
= Negative
The zero pairs are circled. We remove zero pairs!
Step One:
Step Two:
Answer:

6. 6. Represent -4 + 9 in the mat to the right.
Circle the zero pair(s).
How many zero pairs are in the problem ? _____
What is the solution to ? _____
7. Represent 2 + (-3) in the mat to the right.
What is the solution to 2 + (-3) ? _____
8. Represent in the mat to the right.
What is the solution to ? _____
9. Represent 3 + (-5) in the mat to the right.
What is the solution to 3 + (-5) ? _____
10. Why are some answers positive and some answers negative?
How can you predict the sign of the sum (answer) before you actually “do the math”?
12. Write a rule that works for adding integers with different signs.
In your opinion, which method is better– number lines or algebra tiles? Why?

7. Math-7 PRACTICE “ADDITION MODELING”
DATE: ______/_______/_______
NAME:__________________________
“ADDITION MODELING”
Represent the following problems on the given number lines:
= ………..
= ……….
= ……….
= ……….
(-4) = ……….
(-4) = ……….
(-1) = ……….
5 + (-4) = ……….
3 + 6 = ……….
-1 + (-6) = ……….

8. Algebra Tiles Addition
Key:
+ = Positive
- = Negative
Directions: Draw tiles onto below mats in order to model the given problems :
(-3) = _____
(-4) = _____
= _____
(3) = _____
(-2) = _____
(-6) = _____