2.1 Day 3: Multiplying more than two integers Go Math.

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Transcript of 2.1 Day 3: Multiplying more than two integers Go Math.

2.1 Day 3:Multiplying more than two integers

Go Math

• When multiplying many integers, you can multiply from left to right

Multiplying Many Integers

For example,3(-4)(-2)

Do the first two numbers

(-12)(-2)

24

Simplify

-1 (-1)1

Simplify

-1(-1)(-1)1(-1)

-1

Simplify

-1(-1)(-1)(-1)1(-1)(-1)

-1(-1)1

Simplify

-1(-1)(-1)(-1)(-1)1(-1)(-1)(-1)

-1(-1)(-1)1(-1)

-1

Simplify

-1(-1)(-1)(-1)(-1)(-1)1(-1)(-1)(-1)(-1)

-1(-1)(-1)(-1)1(-1)(-1)

-1(-1)1

See a Pattern??

What is the sign when there is an even number of negative

signs?Positive

See a Pattern?

What is the sign when there are an odd number of negative signs?

Negative

Rule:

When multiplying Integers,• If there is an even number of negative factors

the product is positive• If there is an odd number of negative factors

the product is negative

Tell whether the answer is positive or negative

3(2)(-3)Negative

3(-2)(-3)Positive

3(2)(-3)(4)(-1)Positive

5(8)(-4)(2)(-3)(-4)Negative

Try these: Multiply

1.) 15(-9) (-1)Answer will be

positive285(1)

285

2.) -3 (-6)(-2)Answer will be

negative18(2)-36

Homework

• Worksheet