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Some definitions related to integers. |
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Rules for adding and subtracting integers. |
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A method for proving that a rule is true. |
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Positive number – a number greater than zero. |
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Negative number – a number less than zero. |
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Opposite Numbers – numbers that are the same
distance from zero in the opposite direction |
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Integers – Integers are all the whole numbers
and all of their opposites on the negative number line including zero. |
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Absolute Value – The size of a number with or
without the negative sign. |
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If you don’t see a negative or positive sign in
front of a number it is positive. |
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Rule #1 – If the signs are the same, pretend the
signs aren’t there. Add the numbers
and then put the sign of the addends in front of your answer. |
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-3 + -5 = |
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4 + 7 = |
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(+3) + (+4) = |
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-6 + -7 = |
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5 + 9 = |
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-9 + -9 = |
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Rule #2 – If the signs are different pretend the
signs aren’t there. Subtract the smaller from the larger one and put the
sign of the one with the larger absolute value in front of your answer. |
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3 + -5 = |
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-4 + 7 = |
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(+3) + (-4) = |
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-6 + 7 = |
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5 + -9 = |
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-9 + 9 = |
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Rule #1 – If the signs are the same, pretend the
signs aren’t there. Add the numbers
and then put the sign of the addends in front of your answer. |
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Rule #2 – If the signs are different pretend the
signs aren’t there. Subtract the smaller from the larger one and put the
sign of the one with the larger absolute value in front of your answer. |
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