Proofs!!! Ok just little ones :)

Properties of Equality Addition Property –If a = b, then a + c = b + c Subtraction Property –If a = b, then a - c = b - c Multiplication Property –If a = b, then a * c = b * c Division Property –If a = b and c ≠ 0, then

Properties Of Equality Reflexive Property – a = a Symmetric Property –If a = b then b = a Transitive Property –If a = b and b = c then a = c Substitution Property –If a = b, then b can replace a in any expression

Distributive Property If a(b + c) = ab + ac If a(b - c) = ab - ac

Properties of Congruence Definition of Congruence –To move between and equal sign (=) and a congruency sign (  ) you use the Def of  –Note : Properties of equality can only be used with =

Reflexive Property of  Symmetric Property of  Transitive Property of 

Justify Step When solving an equation What is the value of x? Justify each step.

You Try What is the value of x? Justify

Identify the Property Used 1.) 2x + 9 = 19, then 2x = 10 –SPOE 2.) –Transitive POC 3.) –Symm POE

You Try 4.) 5.) 6.) 7.) 1.) Symm POC 2.) Distributive 3.) MPOE 4.) Ref POE

Proofs! A two - Coolum proof is set up with a statements Coolum and a reason Coolum. Each statement follows logically from the above statements.

The End