Transcript Integers REVIEW

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Integer Addition Rules
If the signs are the SAME
Add the numbers. The sign stays the same.
4+3= 7
++++ +++
-7
-4
+
-3
=
_______
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Integer Addition Rules
If the signs are DIFFERENT
Subtract the numbers. The “larger number”
determines the sign of the answer.
-9 + 5 = -4
_ _ _ _ _ _ _ _ _
Subtract the numbers
9 - 5 = 4 Answer -4
+ + + + +
because you started with more negatives
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Subtract Integers
3-2 =1
+ + +
1) Put in 3
2) Take away 2
3) You are left with 1
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Subtract Integers
3 - -2 = 5
+ + +
- - + +
1) Put in 3
2) You can’t take away –2
so add 2 zeros
3) Take away -2
4) You are left with +5
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Subtract Integers
-3 - -2 = -1
_
_
_
1) Put in -3
2) Take away -2
3) You are left with -1
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Subtract Integers
-3 - 2 = -5
_ _ _
_ _
+ +
1) Put in -3
2) You can’t take away 2
so add 2 zeros
3) Take away +2
4) You are left with -5
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Subtract Integers
Keep the first number and
add the opposite.
5 – 6 Is the same as 5 – 6
= -1
SUBTRACT = PLUS CHANGE!
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Subtract Integers
Keep the first number and
add the opposite.
4 – (– 2) Is the same as 4 – (– 2) = 6
SUBTRACT = PLUS CHANGE!
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Subtract Integers
Keep the first number and
add the opposite.
-3 – 1 Is the same as -3 – ( 1) = -4
SUBTRACT = PLUS CHANGE!
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Multiply Integers
2(3) =
Add 2 groups of positive 3.
+++
+++
=6
2(-3) = Add 2 groups of negative 3.
___
___
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= -6
Multiply Integers
-2(3) = Take away 2 groups of positive 3.
+++ +++
= -6
___
___
-2(-3) = Take away 2 groups of negative 3.
+++ +++
___
___
=6
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Divide Integers
When determining the sign, the
rules of multiplying integers are the
same for dividing integers.
If the signs are the same, the
answer is positive. - 64  - 8 = 8
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Divide Integers
When determining the sign, the
rules of multiplying integers are the
same for dividing integers.
If the signs are different, the
answer is negative.
- 8  4 = -2
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Multiply & Divide Integers
When good things, happen to good people, that’s good!
+ • + = +
When bad things, happen to bad people, that’s good!
– • – = +
When good things, happen to bad people, that’s bad!
+ • – = –
When bad things, happen to good people, that’s bad!
–• + = –
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Aren’t integers
interesting?
Take out your
Study Guide!
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#16
Keep the first integer and add the opposite!
TRY
THESE!
1) -3 - - 10 = 7
2) +6 - - 9 = 15
3) -4 - -7 = 3
4) 6 - 8 = -2
5) -3 - - 12 = 9
6) -7 - 12 = -19
7) 5 - -18 = 23
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# 17
-3 - 5 = -8
-15 + 6 = -9
-3 + 5 = +2
-15 - 6 = -21
+3 - 5 = -2
+15 + 6 = +21
+3 + 5 = +8
+15 - 6 = +9
2  3  6
10  2  -5
4  8  32
36  (9)  +4
6(4)  24
27  (3)  -9
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