1. Chapter 2 Section 4 Reasoning in Algebra

2. Properties of Equality Addition Property of Equality If, then. Example: ADD 5 to both sides! Subtraction Property of Equality If, then. Example: SUBTRACT 3 from both sides!

3. Properties of Equality (cont.) Multiplication Property of Equality If, then Example: MULTIPLY both sides by 2! Division Property of Equality If and, then Example:DIVIDE both sides 3!

4. Properties of Equality (cont.) Reflexive Property of Equality A value is equal to itself Symmetric Property of Equality If, then Example: If, then Transitive Property of Equality If and, then

5. Properties of Equality (cont.) Substitution Property If, then can replace in any expression. Example: If then 2 can replace in an expression such as Distributive Property

6. You can justify each statement with a postulate, property, or definition. Solve for, justify each step. Given: A OC B Angle Addition Postulate Substitution Simplify Subtraction Property of Equality Division Property of Equality

7. K N M L StatementsReasons Given Definition of bisect Substitution Subtraction Property of Equality Division Property of Equality Symmetric Property of Equality

8. We can use Segment Addition Postulate to justify statements about segment lengths ACB Solve for y, justify each step. Given: AC=21 StatementsReasons Segment Addition Postulate Substitution Simplify Addition Property of Equality Division Property of Equality

9. Properties of Congruence Reflexive Property of Congruence B A D C A B R V U T S

10. Properties of Congruence Symmetric Property of Congruence Transitive Property of Congruence

11. Name the property of Equality or Congruence that justifies each statement ________________________ _______________________ __________________ Reflexive property of Congruence Addition property of Equality Transitive property of Congruence Symmetric property of Equality