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HW: p. 66-74 #10-13, 38-41 Complete answers: Show your Work!

2.Get a signature on your HWRS3.On desk: math journal, HWRS, pencil

4.Warm Up:

In your journal: 10/23/14Investigation 3: Multiplying and Dividing Rational Numbers

AN 3.2 Multiplication of Rational NumbersWhat algorithm can you use for

multiplying integers?

Positive Factors One Negative Factor

Two Negative Factors

+6+6

- 6

Yes, multiplication is commutative! The order of the factors doesn’t matter.

Positive x Positive = Positive

Positive x Negative = NegativeNegative x Positive = Negative

Negative x Negative = Positive

Positive, 168Negative, -240

Negative, -1

When there are zero or an even number of negative factors , the product is positive!When there is one or an odd number of negative factors, the product is negative!

PositiveNegative

Positive

NegativePositive

When there are zero or an even number of negative factors , the product is positive!When there is one or an odd number of negative factors, the product is negative!

Multiplying Integers - Rules

Positive x Positive = PositivePositive x Negative = NegativeNegative x Positive = NegativeNegative x Negative = Positive

As the number multiplied by 5 decreases by 1, the product decreases by 5

How do the products change as the numbers multiplied by 5 decrease?

With each equation, there is one fewer group of 5. 5 less than 0 is -5 10 less than 0 is -10 15 less than 0 is -15

The product increases each time because you are accumulating fewer negatives (one less group of -4)

Each of the products is the opposite of the product of 4 and a negative number.

Homeworkp. 66-74 #10-13, 38-41

Complete answers: Show your Work!