Accentuate the NegativeInvestigation 3

Multiplying and Dividing Integers

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3.1-2 Introducing Multiplication of Integers

MultiplicationAnd

Division

Algorithm Example

Same Signs Product is positive Quotient is positive

2 x 3 = 6 -2 x -3 = 6 12 ÷ 2 = 6-12 ÷ -2 = 6

Different Signs

Product is negative Quotient is negative

2 x -3 = -6 -2 x 3 = -6 12 ÷ -2 = -6-12 ÷ 2 = -6

‘Multiplication’ Flap of Foldable

Left side

Same Signs• Product is Positive

Ex. 2 x 5 = 10 Ex. -6 x -3 = 18

Right side

Different Signs• Product is Negative

Ex. -7 x 3 = -21 Ex. 2 x -1 = -2

‘Division’ Flap of Foldable

Left side

Same Signs• Quotient is Positive

Ex. 12 ÷ 4 = 3 Ex. -15 ÷ -3 = 5

Right side

Different Signs• Quotient is Negative

Ex. -20 ÷ 10 = -2 Ex. 45 ÷ -15 = -3

Same Signs

• Product is Positive

Ex. 2 x 5 = 10

Ex. -6 x -3 = 18

Different Signs

• Product is Negative

Ex. -7 x 3 = -21

Ex. 2 x -1 = -2

Same Signs

• Product is Positive

Ex. 2 x 5 = 10

Ex. -6 x -3 = 18

Different Signs

• Product is Negative

Ex. -7 x 3 = -21

Ex. 2 x -1 = -2

Same Signs

• Product is Positive

Ex. 2 x 5 = 10

Ex. -6 x -3 = 18

Different Signs

• Product is Negative

Ex. -7 x 3 = -21

Ex. 2 x -1 = -2

Same Signs

• Quotient is Positive

Ex. 12 ÷ 4 = 3

Ex. -15 ÷ -3 = 5

Different Signs

• Quotient is Negative

Ex. -20 ÷ 10 = -2

Ex. 45 ÷ -15 = -3

Same Signs

• Quotient is Positive

Ex. 12 ÷ 4 = 3

Ex. -15 ÷ -3 = 5

Different Signs

• Quotient is Negative

Ex. -20 ÷ 10 = -2

Ex. 45 ÷ -15 = -3

Same Signs

• Quotient is Positive

Ex. 12 ÷ 4 = 3

Ex. -15 ÷ -3 = 5

Different Signs

• Quotient is Negative

Ex. -20 ÷ 10 = -2

Ex. 45 ÷ -15 = -3