Theory:

Adding the opposite of a number to the same number will equal to \(0\) (zero).
Inverse property of addition: For every integer (\(a\)) there exists another opposite integer (\(-a\)) such that:
 
\(a +\) (\(-a\)) \(= 0\).
Example:
\(12\)\(+\)(\(-12\))\(=\)\(0\).
  
Additive inverse of \(a\) is \(-a\).
 
Important!
  • Addition and subtraction are inverse operations of each other.
  • Integers doesn't have multiplicative inverses.