This document contains notes from a math lesson on multiplying and dividing integers: 1) It provides rules for multiplying integers based on the signs of the numbers, and examples of multiplying integers. 2) It then provides rules for dividing integers based on the signs of the numbers, and examples of dividing integers. 3) The final page lists homework problems assigning students to complete selected even problems from page 47 and problems 61-65.

1. 1.9 mult and div integers August 25, 2011
Bellwork
Each student on a committee of 5 students shakes hands
with every other committee member.
1. Construct a diagram to represent the pattern.
2. Draw and complete a table representing the pattern.
3. How many handshakes will there be in all?
4. 5 9 5. 2 4
27 35 21 7
HW pg. 47 #2­28 evens, 61­65 1

2. 1.9 mult and div integers August 25, 2011
HW pg. 47 #2­28 evens, 61­65 2

3. 1.9 mult and div integers August 25, 2011
1.9 Multiplying Integers
The product of 2 #s with same sign is +.
The product of 2 #s with different signs is -.
The product of 0 and any # is 0.
3 (4) 3(-4)
-3(-4) -3(4)
3(0) -4(0)
HW pg. 47 #2­28 evens, 61­65 3

4. 1.9 mult and div integers August 25, 2011
-3(5)(-4)
6(-3)(5)
HW pg. 47 #2­28 evens, 61­65 4

5. 1.9 mult and div integers August 25, 2011
1.9 Dividing Integers
The quotient of 2#s with same sign is +.
The quotient of 2#s with different signs is -.
Division by 0 is undefined (does not work).
12/3 12/-3
-12/-3 -12/3
HW pg. 47 #2­28 evens, 61­65 5

6. 1.9 mult and div integers August 25, 2011
-32/8
-56/-4
HW pg. 47 #2­28 evens, 61­65 6

7. 1.9 mult and div integers August 25, 2011
HW:
pg. 47
#2-28
evens,
61-65
HW pg. 47 #2­28 evens, 61­65 7