Lesson 2.4 AIM: Properties of Equality and Congruence DO NOW: Draw a conclusion from the following statements. 1. If an integer ends in 4, it is divisible.

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Presentation transcript:

Lesson 2.4 AIM: Properties of Equality and Congruence DO NOW: Draw a conclusion from the following statements. 1. If an integer ends in 4, it is divisible by If an integer is divisible by 2, it is even. CONCLUSION: If an integer ends in 4, it is even.

The Reflexive Property states I am as tall as myself.

The Symmetric Property states If I am as tall as my brother, my brother is as tall as me.

The Transitive Property states If I am as tall as my brother, and my brother is as tall as my cousin, I am as tall as my cousin.

Name the Property a.Symmetric Property b.Reflexive Property c.Transitive Property

Prove MN = PQ STATEMENTJUSTIFICATION

Prove MN = PQ STATEMENT 1. MN = NP JUSTIFICATION 1. Definition of Midpoint

Prove MN = PQ STATEMENT 1.MN = NP 2. NP = PQ JUSTIFICATION 1. Definition of Midpoint 2. Definition of Midpoint

Prove MN = PQ STATEMENT 1.MN = NP 2. NP = PQ 3. MN = PQ JUSTIFICATION 1. Definition of Midpoint 2.Definition of Midpoint 3.Transitive Property

Prove Angle 1 is Congruent to Angle 2 STATEMENTJUSTIFICATION

Prove Angle 1 is Congruent to Angle 2 STATEMENT 1.A 1 + A 3 = 180 JUSTIFICATION 1. Definition of Supplementary

Prove Angle 1 is Congruent to Angle 2 STATEMENT 1.A 1 + A 3 = A 2 + A 3 = 180 JUSTIFICATION 1. Definition of Supplementary 2. Definition of Supplementary

Prove Angle 1 is Congruent to Angle 2 STATEMENT 1.A 1 + A 3 = A 2 + A 3 = A 1 + A 3 = A 2 + A 3 JUSTIFICATION 1. Definition of Supplementary 2. Definition of Supplementary 3.Substitution Property

Prove Angle 1 is Congruent to Angle 2 STATEMENT 1.A 1 + A 3 = A 2 + A 3 = A 1 + A 3 = A 2 + A 3 - A 3 - A 3 JUSTIFICATION 1. Definition of Supplementary 2. Definition of Supplementary 3.Substitution Property

STATEMENT 1.A 1 + A 3 = A 2 + A 3 = A 1 + A 3 = A 2 + A 3 - A 3 - A 3 4. A1 = A2 JUSTIFICATION 1. Definition of Supplementary 2. Definition of Supplementary 3.Substitution Property 4. Subtraction Property of Equality Prove Angle 1 is Congruent to Angle 2

Summary Question Identify the following property: If AB = BC and BC = CD, then AB = CD.