How can you classify the results of operations on real numbers?

Closure property: If a and b are real numbers, a+b is also a real number.
- Associative property: a+(b+c) = (a+b)+c.
- Commutative property: a+b = b+a.
- Additive identity: a+0 = a.
- Additive inverse: a + (-a) = 0.
For Multiplication -

A squared plus B squared equals C squared