Multiplying Integers Multiplying Integers Lets model integer multiplication

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Multiplying Integers

Multiplying Integers

Multiplying Integers • Let’s model integer multiplication: -6 • 5 = -30 2 •

Multiplying Integers • Let’s model integer multiplication: -6 • 5 = -30 2 • -3 = -6

Multiplying Integers So, a positive number times a negative number is a ____ number.

Multiplying Integers So, a positive number times a negative number is a ____ number. Negative And, a negative number times a positive number is a ____ number. Negative What is the answer to a negative times a negative?

Multiplying Integers • Look at the pattern: -2 • 3 = -6 -2 •

Multiplying Integers • Look at the pattern: -2 • 3 = -6 -2 • 2 = -4 -2 • 1 = -2 -2 • 0 = 0 -2 • -1 = ? ? What is happening to the product each time? It is increasing by 2 -2 • -1 = 0 + 2 which is 2

Multiplying Integers A negative number times a negative number is a ____ number Positive

Multiplying Integers A negative number times a negative number is a ____ number Positive

Multiplying Integers Here is a way to remember it: Good guys are +, Bad

Multiplying Integers Here is a way to remember it: Good guys are +, Bad guys are – Coming into town is +, Leaving Town is – Good is +, Bad is If a good guy (+) comes into town (+), that’s good (+) If a good guy (+) leaves town (-), that’s bad (-) If a bad guy (-) comes into town (+), that’s bad (-) If a bad guy (-) leaves town (-), that’s good (+)

Multiplying Integers • Multiply: 4(-3) -12 -2 • -9 18 (-25)(6) -150 -7 •

Multiplying Integers • Multiply: 4(-3) -12 -2 • -9 18 (-25)(6) -150 -7 • -32 224 12(10) 120 -16(-5) 80

The Integer Song Verse 4 Here is a rule that you must know when

The Integer Song Verse 4 Here is a rule that you must know when multiplying integers, If signs are the same The answer’s always positive.

The Integer Song Verse 5 Another rule that you must know when multiplying integers,

The Integer Song Verse 5 Another rule that you must know when multiplying integers, If signs are different The answer’s always negative.