MULTIP

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RULES

When multiplying integers with like (the same) signs, the product (answer) will be positive.

EX.) negative x negative = positive

positive x positive = positive

5 * 3 = ____

(-5) * (-3) = ____

When multiplying integers with different signs, the product (answer) will be negative.

EX.) negative x positive = negative

positive x negative = negative

(-5) * 3 = ____

5 * (-3) = _____

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PRACTICE

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MULTIPLYING WITH MORE THAN TWO FACTORSWhen multiplying more than two factors, count the number of

negative integers:

*If you have an odd number of negative integers, then your product (answer) will also be negative.

*If you have an even number of negative integers, then your product (answer) will be negative.

TRY THESE:

Negative Positive Positive Negative

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MULTIPLYING WITH VARIABLES

Sometimes you will be asked to simplify. Sometimes you will be asked to evaluate.

• When asked to simplify, you will not be able to solve the problem out to a numerical answer. Your answer will have a variable in it.

• Multiply your coefficients first; then combine your variables• EXAMPLE: 3a * (-5b) = -15ab

• When asked to evaluate, you need to substitute each variable for the values given and solve based on the rules for multiplying integers.

• Be careful to substitute what is given for each value.• EXAMPLE: x = -4, y = 3 -xy = 12 - (-4) * 3 4 * 3 = 12

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