Reflexive Property: A number or expression is equal to itself. For any number a, a=a.

Symmetric Property: The sides of an equation can be switched around. If a=b, then b=a for any numbers a and b.

Transitive Property: If a number is equal to a second number and the second number is equal to the third number. Then the first number is equal to the third number. If a=b and b=c then a=c for all numbers a, b, and c.

Substitution Property: If two quantities are equal then they can be replaced with each other in any expression.