Multiplying Integers

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Multiplying Integers

• Objective Multiplying integers

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Multiplying Rules

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

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2-6 Multiplying Integers
Example 2 Solve p -7(11) p -7(11) The two
factors have different signs.
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2-6 Multiplying Integers
Example 2 Solve p -7(11) p -7(11) The two
factors have different signs. p -77 The
product is negative.
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2-6 Multiplying Integers
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2-6 Multiplying Integers
Example 3 Solve r -8(-9) The two factors have
the same sign.
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2-6 Multiplying Integers
Example 3 Solve r -8(-9) r -8(-9) The two
factors have the same sign. r 72 The product
is positive.
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Examples 1) (3x)(-8y)
-24xy
Write both numbers as a fraction. Cross-cancel if
possible.
Multiplying fractions top top Bottom
bottom
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When multiplying two negative numbers, the
product is negative.

• True
• False

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

• True
• False

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2-6 Multiplying Integers
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an easy way to determine the sign of the answer
When you have an odd number of negatives, the
answer is negative. When you have an even number
of negatives, the answer is positive.
4) (-2)(-8)(3)(-10) Do you have an even or odd
number of negative signs?
3 negative signs -gt Odd -gt answer is negative -480
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Positive or negative answer? Positive - even of
negative signs (4)
Write all numbers as fractions and multiply.
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What is the sign of the product of
(-3)(-4)(-5)(0)(-1)(-6)(-91)?

• Positive
• Negative
• Zero
• Huh?

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2-6 Multiplying Integers
Example 4 Solve q -2(-3)(-11) q
-2(-3)(-11) There are three negative factors. q
-2(-3)(-11) Three is odd.
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2-6 Multiplying Integers
Example 4 Solve q -2(-3)(-11) q
-2(-3)(-11) There are three negative factors. q
-2(-3)(-11) Three is odd. q -2(33) q
-66
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2-6 Multiplying Integers
Example 4 Solve q -2(-3)(-11) q
-2(-3)(-11) There are three negative factors. q
-2(-3)(-11) Three is odd. q -2(33) q
-66 The product will be negative.
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Multiply (-3)(4)(-2)(-3)

• 72
• -72
• 36
• -36