Question

ho do i add two numbers that arenthe sme but one is posotive while the other negative -3+3

Answer 1

-3 plus 3 we be 0. -3-3 would be negative 6 

Answer 2

If you just write them in the other direction  ==>    +3 - 3
you'll see that it's just a simple subtraction problem.

With these particular numbers, the result is zero.