Kim's Inverse Property

example:
4 - 3 = 1

to change that into a addition problem you would have to change the subtraction sign into a addition sign

4 + 3

That isn't it. After you put in the addition sign, you have to turn the 3 into a negative.
The problem would now be

4 + (-3) = 1


http://mathforum.org/dr.math/faq/faq.property.glossary.html