1. Section 2-4: Adding Integers using Rules
Objective: Add Integers using Rules

2. Adding Integers
We are going to predict patterns and make rules based on what we notice.
Then, we are going to simplify variable expressions.

3. Adding Integers
Solve the problems by using + and – to show your work.
4 + 5
Predict: What do you notice about your answers? What rule can we make?

4. + + + = + Adding Integers Rule 1:
Adding positives will give you a positive.
= +

5. Adding Integers -12 + (-3) -5 + (-17)
Solve the problems by using + and – to show your work.
-12 + (-3)
-5 + (-17)
Predict: What do you notice about your answers? What rule can we make?

6. - + - = - Adding Integers Rule 2:
Adding negatives will give you a negative.
= -

7. Adding Integers -5 + 8 -6 + 13 10 + (-7)
Solve the problems by using + and – to show your work.
-5 + 8
10 + (-7)
Predict: What do you notice about your answers? What rule can we make?

8. + + - = + Adding Integers Rule 3:
Adding a BIGGER positive and smaller negative will give you a positive.
TAKE THE SIGN OF THE NUMBER WITH THE
BIGGER ABSOLUTE VALUE (BIGGER
DISTANCE FROM ZERO.
+ + - = +

9. Adding Integers -4 + 1 -11 + 3 12 + (-17)
Solve the problems by using + and – to show your work.
-4 + 1
12 + (-17)
Predict: What do you notice about your answers? What rule can we make?

10. Adding Integers + + - = - Rule 4:
Adding a smaller positive and BIGGER negative will give you a NEGATIVE.
TAKE THE SIGN OF THE NUMBER WITH THE
BIGGER ABSOLUTE VALUE (BIGGER
DISTANCE FROM ZERO.
+ + - = -

11. Adding Integers
Solve.
4 + (-11)
6 + (-2) (-8)

12. Simplify Expressions Simplify the expressions by combining like terms.
4n + (-6n) + 3
21w + (-17w) + 6w
5x + (-2x) + 7

13. Evaluate Expressions
Evaluate (solve) by combining like terms and substituting.
-5x + 14x + (-6x) when x = 2
8x + (-7) + (-5x) when x = 2