Multiplication of Real Numbers

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Section 2.5

• Multiplication of Real Numbers

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Multiplying Rules

• 1) If the numbers have the same signs then the
  answer is positive.
• (-7) (-4) 28
• 2) If the numbers have different signs then the
  answer is negative.
• (-7) 4 -28

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Examples 1) (3x)(-8y)
-24xy
Write both numbers as a fraction.
Multiplying fractions (multiply across)
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When multiplying two negative numbers, the
product is negative.

1. True
2. False

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When multiplying a negative number and a positive
number, use the sign of the larger number.

1. True
2. False

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(No Transcript)
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Multiply (-3)(4)(-2)(-3)

1. 72
2. -72
3. 36
4. -36

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Examples 1. 2. 3.
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What is the sign of the product of
(-3)(-4)(-5)(0)(-1)(-6)(-91)?

1. Positive
2. Negative
3. Zero
4. No stinkin clue