1. Properties of Equality
Notes 2.5
Properties of Equality

2. Addition and Subtraction Properties of Equality
If a = b, then a + c = b + c
If a = b, then a - c = b - c

3. Multiplication and Division Properties of Equality
If a = b, then ac = bc
If a = b, then a/c = b/c

4. Reflexive Property of Equality
a = a Anything equals itself

5. Symmetric Property of Equality
If a = b, then b = a
Mirror Image

6. Transitive Property of Equality
If a = b and b = c, then a = c

7. Substitution Property of Equality
If a = b, then b may be substituted for a in any expression.

8. Distributive Property of Equality
a(b + c) = ab + ac
a(b – c) = ab - ac

9. Given: 2x+5 = 17 Prove x = 6 Statement Reason 1) 2x + 5 = 17 1) Given
2) Subtract =
3) X = 6
3) Division =

10. Given: 4x+5 = 6x - 9 Prove x = 7 Statement Reason 1) 4x + 5 = 6x - 9
2) Subtract =
3) 14 = 2x
3) Add =
4) Division =
4) X = 7