What's the Addition Property of Equality?

To preserve an equality, what you do to one side of the equality must be done to the other side of the equality
'a', 'b', and 'c' are just variables representing numbers
'a = b' is an equality

1. An equality is just two algebraic expressions combined by an equal sign
2. An algebraic expression is a properly-formed combination of mathematical symbols that does not contain an equality sign
1. An equality is just two algebraic expressions combined by an equal sign
2. An algebraic expression is a properly-formed combination of mathematical symbols that does not contain an equality sign
3. Remember that variables can represent numbers, so you can substitute "variable" for "number" here and it would mean the same thing
1. 'a', 'b', and 'c' are just variables representing numbers here
2. Adding 'c' is one of many operations that could have been performed on the equality
1. An equality is just two algebraic expressions combined by an equal sign
2. An algebraic expression is a properly-formed combination of mathematical symbols that does not contain an equality sign

Definition: Addition Property of Equality