Properties of Equality Notes 2.5 Properties of Equality
Addition and Subtraction Properties of Equality If a = b, then a + c = b + c If a = b, then a - c = b - c
Multiplication and Division Properties of Equality If a = b, then ac = bc If a = b, then a/c = b/c
Reflexive Property of Equality a = a Anything equals itself
Symmetric Property of Equality If a = b, then b = a Mirror Image
Transitive Property of Equality If a = b and b = c, then a = c
Substitution Property of Equality If a = b, then b may be substituted for a in any expression.
Distributive Property of Equality a(b + c) = ab + ac a(b – c) = ab - ac
Given: 2x+5 = 17 Prove x = 6 Statement Reason 1) 2x + 5 = 17 1) Given 2) Subtract = 3) X = 6 3) Division =
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