1. A bakery can bake 12 dozen cookies in 12 minutes. If the bakery’s pace stays the same, how many cookies can it bake in 1 ½ hours? Bellringer

2. Multiplication of Integers

3.  TLW compute fluently with multiplication of integers.

4. Negative Times Negative is What?  Some people think of negative as meaning “not.”  Consider the sentence: “I am not going to the store.”  It is the negative version of “I am going to the store.”

5. So what do two “nots” mean?  Consider this sentence: “You may tell me NOT to go to the store, but I’m not going to do what you say!”

6.  The two “nots” cancel each other out, just like two negatives.  I am insisting that I WILL go to the store!

7. Deposits and Withdrawals  A positive integer is like a deposit, and a negative integer is like a withdrawal.

8. Transaction Representation Add 3 deposits of $100 (3)(100) Increase of $300 Result

9. Transaction Representation 4 withdrawals of $20 (4)(-20) Decrease of $80 Result

10. Symbolism = love = hate

11. Character Symbolism  If you love to love means you love. X = Pos. X Pos. = Pos.

12.  If you hate to hate means you love. X = Neg. X Neg. = Pos.

13.  If you love to hate means you hate. X = Pos. X Neg. = Neg.

14.  If you hate to love means you hate. X = Neg. X Pos. = Neg.

15. Multiplying Two Integers  (+7)(+3) =  (-7)(-3) =  (+7)(-3) =  (-7)(+3) = +21 -21

16. Multiplying Three Integers (+5)(+3)(+2) = (+15)(+2) = +30

17. Multiplying Three Integers (+5)(+3)(-2) = (+15)(-2) = -30

18. Multiplying Three Integers (-5)(-3)(-2) = (+15)(-2) = -30

19. CHECK IT OUT! Is the product positive or negative when an odd number of negative numbers are multiplied? NEGATIVE

20. RULES  When multiplying an ODD number of negatives, the product is always NEGATIVE.  When multiplying an EVEN number of negatives, the product is always POSITIVE.