1. Multiplication and Division of Integers

2. Cornell Notes objective I will add integers… Origin 9/11/06 Notes
The point on the
line labeled zero
Summary or questions

3. Hey- your idea was great!
Share out…
If your partner had an idea about multiplying or dividing with negative numbers, please share their thought.
Hey- your idea was great!

4. Here’s a way I can Remember!
To remember whether your answer will be positive or negative when MULTIPLYING or DIVIDING, we’ll use:
Mr. Multiplivision

5. = -15 What sign is left uncovered? When multiplying
Integers, cover the
Two signs you are using
Choral Response
What sign is left
uncovered?
Ex.: 5 (-3)
Negative, -
That is the sign of
The answer
= -15

6. Practice … under time! (-10)(3) = 21  -5 = -13  -6 =
(raffle tickets…)
(-10)(3) =
21  -5 =
-13  -6 =

7. 1:00

8. Division
It’s not any different!
Good News:
Ex.: -48  (-4)
= + 12

9. Reminder:
Equal means it works both ways! 

10. “Boss” and “Secretary”
Person B: Boss first
Partner A: Secretary first
Tell the “secretary” what to write in solving
Copy exactly what boss says
Turn to your neighbor: Person on the left: what’s good about this
Right: What’s the bad consequence of this
Response: They can copy notes, vocab, etc. while holding another conversation, thinking about the weekend, etc.
Cornell notes: questions, summaries
Frayer model- student worded definition
Good News + It”s easy to get their attention with ANY thing different
Think Pair Share
SOLVE:
(4)(-7)  (-2)
Then switch!

11. Grade your boss’ work… Answer: 14 (4)(-7)  (-2) First, (4)(-7) = - 28
Finish it! (-28)(-2)
Answer: 14

12. = 4
(-56  7)  - 2
5  -7  -6
= 210
= - 135

13. Why does it all work?

14. Properties of Multiplication
Identity a  1 = a and 1  a = a
Zero Property a  0 = 0 and 0  a = 0
Property of -1 a(-1) = -a and (-1)a = -a

15. Distributive Property
How will we use this with
integer multiplication?
a (b+c) = ab + bc
-1 (5 + 7) = (-1)5 + (-1)7
Also, -7
= (-1) 7

16. Here’s How to Use It
Ex.: (-7) 6
(-1) (7 6) = - 42

17. (-1)(-1) = ?
= 1
Why??

18. Vocabulary Reciprocal: Two numbers whose product is 1.
Ex.: reciprocal of a:

19. More on Reciprocal
Ex.:
= -2