Adding, Subtracting, Multiplying, and Dividing Integers

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NO CALCULATORS!!!!!!!
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Integers are the whole numbers and their
opposites (no decimal values!)
Example: -3 is an integer
Example: 4 is an integer
Example: 7.3 is not an integer
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Adding integers comes down to two rules
Rule 1: If the signs (+ or -) are the same, simply
add the numbers and keep that value
Example: -4 + -8 = -12 (because 4 + 8 is 12)
Rule 2: If the signs are different, simply
subtract the number closest to zero from the
number further away from zero and keep the
sign of the number furthest from zero
Example: 3 + -7 = -4 (because 7 – 3 is 4)
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Subtraction and addition are friends, so
subtraction just changes itself to addition by
changing the second number’s sign. Make sure
you follow the addition rules after that.
Example: -4 – 6 means -4 + -6 = -10
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They, too, are friends so they share the rules
Rule 1: When the signs are the same (either + +
or - -) simply do the operation and the answer
will be positive
Example: -25 ÷ -5 = 5 (since it is - -)
Rule 2: When the signs are different (either + or - +) simply do the operation and the answer
will be negative
Example: -4 • 8 = -32 (since it is - +)
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-5 + 8
3
-11 – 4
-15
7 • -4
-28
-36 ÷ 9
-4
-3 + 2
-1
15 – (-2)
17
-8 • -3
24
12 ÷ -4
-3
-11 + -4
-15
-1 – (-6)
5
-11 • 2
-22
-28 ÷ -7
4
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