what are the rules for adding and subtracting rational numbers

Question

what steps would you take to add or subtract a negative or positive number

Answer 1

In some ways they are both adding.  If you are subtracting a number, what you are really doing is adding a negative.

 

3-2=1 which is the same as 3+(-2)=1

 

Once you know this you can use the fact that for addition it doesn't matter which order the numbers are in (just remember to carry the sign over with you)

6-10 means the same as 6+(-10) so I can rewrite it as -10+6 so I am stating at -10 and moving 6 places on the number line to the right (addition always moves to the right) so I get to -4

You can think of it as losses (negative) and gains (positives) if you add a loss to a loss you have a greater loss so the answer will be a smaller number than the ones you started with if you add a gain to a loss you have more than you started with.

Answer 2

x     y

0     3

1     -1

2    -5

3     -9

4     -13

find a function rule for each table of values