Additive Inverses are 2 opposite integers. One positive and one negative
Ex: ‐2 and 2
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Additive Inverse Property ‐ The sum of any number and its additive inverse is 0.
Ex: ‐2 + 2 = 0
‐7 + 7 = 0
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Adding Integers with the same sign
• The sum of two positive integers is positive
• the sum of two negative integers is negative
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Adding Integers with different signs:
To add integers with different signs, subtract the absolute value:
• The sum is positive if the positive number has a larger absolute value
• The number is negative if the negative integer has
a greater absolute value
w = ‐40 + 15
/‐40/ > /15/ ‐ so the sum is negative
40 ‐ 15 = 25
The answer is ‐25.
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Evaluate: ‐13 + a = if a = 28
‐13 + 28 = n
/‐13/ < /28/ so the answer will be positive
28 ‐ 13 = 15
the answer is 15
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