1. Interesting Integers! Adding
What You Will Learn
Rules for adding integers.
A method for proving that a rule is true
Are you ready??

2. Integer Addition Rules
Rule #1 – If the signs are the same, pretend the signs aren’t there. Add the numbers and then keep the same sign.
9 + 5 = 14
= -14

3. Solve the Problems -3 + -5 = 4 + 7 = (+3) + (+4) = -6 + -7 = 5 + 9 == -8 11 7
-13 14
-18

4. =
2. – = =
4. – =

5. Integer Addition Rules
Rule #2 – If the signs are different pretend the signs aren’t there. Subtract the smaller from the larger one and put the sign of the one with the larger absolute value in front of your answer. =
Larger abs. value
Answer = - 4
9 - 5 = 4

6. Solve These Problems -2 3 + -5 = -4 + 7 = (+3) + (-4) = -6 + 7 == =
5 – 3 = 2
7 – 4 = 3 3
4 – 3 = 1 -1
7 – 6 = 1 1
9 – 5 = 4 -4
9 – 9 = 0

7. Signs same – add and keep.
Different – just subtract.
Keep the sign of the bigger one – then it will be exact.
(sing to the tune of row row row your boat)

8. 1. – =
2. – =
(-7) =
4. – =

9. One Way to Add Integers Is With a Number Line
When the number is positive, count
to the right.
When the number is negative, count
to the left. - + 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6

10. One Way to Add Integers Is With a Number Line= -2 + 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 -

11. One Way to Add Integers Is With a Number Line= +2 + 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 -

12. One Way to Add Integers Is With a Number Line= -4 + 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 -

13. One Way to Add Integers Is With a Number Line= +4 - 1 2 3 4 5 6 -1 -2 -3 -4 -5 -6 +

14. Ready to practice?
Let’s go out in the hallway and use a big number line to solve some problems.

15. Working with your shoulder partner, solve the problems on the paper
Working with your shoulder partner, solve the problems on the paper. Use the sage and scribe method – person 1 tells partner what to do while person 2 writes (praising or correcting). Then switch roles for next problem. Follow this procedure until you have the circled problems in column 1 completed.

16. Homework:
pg evens
Read pages 63 and 64