Integer operations

ADDITION Same signs
If you had

-3+-6.

First you'd start at zero then move three spaces to the left
to get to -3 like in the problem. Then you would move six
more spaces to the left to get -9 as your answer.


ADDITION with different signs


If you had

4+-7.


You'd first start by starting on the zero. Then you move to
the right four spaces to get +4. But then you would go left seven
spaces to get -3 as your answer.




SUBTACTING with the same signs


If you had

3-8


First you'd go to the right three spaces like in the problem.
Then you would go to the left eight spaces to get -5.



SUBTACTING with diffreent signs


If you had

-4-2

First you start at the zero. Then you'd move to the left
four spaecs to be at -4 like in the problem. Then to subtact
make two moves to the left two times, to get your answer of
-6.


MULTIPLUING with the same signs


If you had

-4x-2

First you'd think what 4x2 is and it is
eight. But if the signs are the same the product
is positive.

-4x-2
-4x-2=8



MULTIPLYING with different signs



If you had

3x-3

First you think 3x-3 means three groups of
-3.

3x-3= -3 + -3 +-3



DIVIDING with the same signs


If you had

-100/-5

First you'd think of what -100/-5is. It is 20. So the signs
are the same the quotient is positive.

-100/-5
-100/-5
20


DIVIDING with the different signs




If you had

72/-9

First you would think of what 72/-9 is. It is 8. So the signs
are different the quotient is negative.



RULES!

Additon rules:
If the signs are the same then add and keep
the signof the number.

If the signs are different then subtact and
keep the sign of the bigger number.

Subtaction rules:
Change all subtaction to addition by doing
the plus the oppisit of the end.

Multiplution and Dividing:

Same signs: positive
Different signs: negative

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