How do u find the difference between points

Do u just add or subtract if it is positive or negitive numbers

You draw a number line.

you start at the first number and then go right if you are adding the next number or you go left if you are subtracting the next number

-3+9    

Start at the -3  then go 9 in the positive direction.      -2,-1,0,1,2,3,4,5,6         The answer is 6

Oh, in your title you asked for difference.

Difference means take away.

Just remember that if you take away a negative number then you are really adding

6 - - 7 = 6 + 7 = 13

-5 - + 8 = -5 -8 = -13

5 - + 8 = 5 - 8 = -3