This document provides examples and explanations for multiplying and dividing integers: 1) It shows examples of multiplying integers through repeated addition or subtraction, and notes that the sign of the sum depends on the signs of the integers being multiplied. 2) It explores patterns that emerge when multiplying integers, such as a positive integer multiplied by a negative integer equals a negative product. 3) It suggests that dividing integers will follow predictable patterns based on what was observed with multiplication, such as a positive number divided by a negative number equals a negative quotient. The document aims to build understanding of integer multiplication and division through worked examples and identifying patterns and rules.

1. AIM: Multiplying and Dividing
Integers
Do Now
Evaluate the following expression.
a.) -3 - 5 + (-4) - (-2)
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2. Multiplication Repeated Addition Sum
3 (-5) -5 + ( -5 ) + ( -5) - 15
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3. Multiplication Repeated Addition Sum
3 (-5) -5 + ( -5 ) + ( -5) - 15
5 (-4)
2 (-8)
4 (-10)
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4. Multiplication Repeated Addition Sum
3 (-5) -5 + ( -5 ) + ( -5) - 15
2. What do you notice about the signs of the sums?
3. What do these examples suggest about the product of a
positive and a negative integer?
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5. Think-Pair-Share Activity:
Multiply
4.) -5 2 5.) -4 7 6.) 9 (-8)
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6. Use the pattern to find each product.
2(-5) =
1(-5) =
0(-5) =
-1(-5) =
-2(-5) =
­10 ­9 ­8 ­7 ­6 ­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5 6 7 8 9 10
What conclusion about a negative number multiplied
by a negative number based on this pattern?
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7. Multiply.
9.) -5 (-5) 10.) -3 (-4)
11.) -3 4 (-5) 12.) -8 (-6) (-2)
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8. 13.) Based on what we have explored with multiplying integers,
what predictions can you make about dividing integers?
Divide
14.) -500 ÷ (-10) 15.) 48 ÷ (-6)
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9. Evaluate the following expressions for:
a = -3, b = 5, and c = -8
1.) -3c + b 2.) 5a - b c.) ab + c
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10. 16.) -5 • 4 + (-40) ÷ (-10)
17.) -3[(6 - 10) ÷ (-2)]
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11. Extra Practice
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12. BEFORE YOU LEAVE (Part 1)
18.) Find the mean of the differences in the values of a Canadian
dollar and a US dollar for 1994 - 1998. The differences were -27
cents, -27 cents, -26 cents, -28 cents, -32 cents.
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13. BEFORE YOU LEAVE (Part 2)
19.) Find the mean of 4, -3, -5, 2, -8.
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14. Homework
Castle Homework #2
due tomorrow
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15. AIM: Multiplying and Dividing
Integers
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