1. Multiplying and Dividing Integers
Intro Video
(Click Here)
Multiplying and Dividing Integers

2. Multiplying and Dividing Integers
Lesson 1.4/1.5
Multiplying and Dividing Integers

3. How to Determine the Correct Sign
Same signs give a positive product
Different signs give a negative product + - -

4. - + Examples: If you don’t see an operation, then multiply. A) 4(-2)
So, this is the same as
4 • (-2)
What is the sign of the product? + - – 8
What is 4 • 2?

5. Examples: B) -8(-5) + 40 or 40 Same signs give a positive product
Different signs give a negative product
B) -8(-5) + 40 or 40

6. You try these!
C) (-9)(-2)
E) 8(-4) 18
-32
D) 11(-1)
F) -7(-7)
-11 49

7. Multiplying Many Integers
When multiplying many integers, you can multiply from left to right
For example,
3(-4)(-2)
Do the first two numbers
(-12)(-2) 24

8. Dividing Integers

9. -1 + (-2) + (-3) + (-4) + (-4) + (-4)
Mean Means Average
To find the average, you add up all of the numbers and divide by the number of added items.
Find the average -1 -2 -3 -4
-1 + (-2) + (-3) + (-4) + (-4) + (-4) 6
-18
= -3 6

10. Discussion
1) Find the average of the feet above and below sea level: 135, -56, 92, -29, -88, -60
135 + (-56) (-29) + (-88) + (-60) 6 -6
= -1 6

11. Video PBS Math Club

12. Homework
BI: Page 26 (4-30) even
BI: Page 32 (6-32) even