# SSS SAS ASA AAS Proving Triangles Congruent The

- Slides: 55

SSS, SAS, ASA, & AAS

Proving Triangles Congruent

The Idea of a Congruence Two geometric figures with exactly the same size and shape. F B A C E D

How much do you need to know. . . about two triangles to prove that they are congruent?

Corresponding Parts You learned that if all six pairs of corresponding parts (sides and angles) are congruent, then the triangles are congruent. B 1. AB DE 2. BC EF 3. AC DF 4. A D 5. B E 6. C F A C ABC DEF E F D

Do you need all six ? NO ! SSS SAS ASA AAS

Side-Side (SSS) B E F A C 1. AB DE 2. BC EF 3. AC DF D ABC DEF

Side-Angle-Side (SAS) B E F A C 1. AB DE 2. A D 3. AC DF D ABC DEF included angle

Included Angle The angle between two sides G I H

Included Angle Name the included angle: E Y S YE and ES E ES and YS S YS and YE Y

Angle-Side-Angle (ASA) B E F A C 1. A D 2. AB DE D ABC DEF 3. B E included side

Included Side The side between two angles GI HI GH

Included Side Name the included side: E Y S Y and E YE E and S ES S and Y SY

Angle-Side (AAS) B E F A C 1. A D 2. B E D ABC DEF 3. BC EF Non-included side

Warning: No SSA Postulate There is no such thing as an SSA postulate! E B F A C D NOT CONGRUENT

Warning: No AAA Postulate There is no such thing as an AAA postulate! E B A C D NOT CONGRUENT F

The Congruence Postulates F SSS correspondence F ASA correspondence F SAS correspondence F AAS correspondence F SSA correspondence F AAA correspondence

Name That Postulate (when possible) SAS SSA ASA SSS

Name That Postulate (when possible) AAA SAS ASA SSA

Name That Postulate (when possible) Reflexive Property SAS Vertical Angles SAS Reflexive Property SSA

HW: Name That Postulate (when possible)

HW: Name That Postulate (when possible)

Let’s Practice Indicate the additional information needed to enable us to apply the specified congruence postulate. For ASA: B D For SAS: AC FE For AAS: A F

HW Indicate the additional information needed to enable us to apply the specified congruence postulate. For ASA: For SAS: For AAS:

Write a congruence statement for each pair of triangles represented. D B A E C F

Slide 1 of 2

Slide 1 of 2

Before we start…let’s get a few things straight C A Y B X INCLUDED SIDE Z

Angle-Side-Angle (ASA) Congruence Postulate Two angles and the INCLUDED side

Angle-Side (AAS) Congruence Postulate Two Angles and One Side that is NOT included

Your Only Ways To Prove Triangles Are Congruent

Things you can mark on a triangle when they aren’t marked. Overlapping sides are congruent in each triangle by the REFLEXIVE property Vertical Angles are congruent Alt Int Angles are congruent given parallel lines

Ex 1 DEF NLM

Ex 2 What other pair of angles needs to be marked so that the two triangles are congruent by AAS? D L M F E N

Ex 3 What other pair of angles needs to be marked so that the two triangles are congruent by ASA? D L M F E N

Determine if whether each pair of triangles is congruent by SSS, SAS, ASA, or AAS. If it is not possible to prove that they are congruent, write not possible. Ex 4 G K I H J ΔGIH ΔJIK by AAS

Determine if whether each pair of triangles is congruent by SSS, SAS, ASA, or AAS. If it is not possible to prove that they are congruent, write not possible. Ex 5 B A C D E ΔABC ΔEDC by ASA

Determine if whether each pair of triangles is congruent by SSS, SAS, ASA, or AAS. If it is not possible to prove that they are congruent, write not possible. Ex 6 E A C B D ΔACB ΔECD by SAS

Determine if whether each pair of triangles is congruent by SSS, SAS, ASA, or AAS. If it is not possible to prove that they are congruent, write not possible. Ex 7 J M K L ΔJMK ΔLKM by SAS or ASA

Determine if whether each pair of triangles is congruent by SSS, SAS, ASA, or AAS. If it is not possible to prove that they are congruent, write not possible. Ex 8 J T K L V Not possible U

Slide 2 of 2

Slide 2 of 2

Slide 2 of 2

Slide 2 of 2

(over Lesson 5 -5) Slide 1 of 2

(over Lesson 5 -5) Slide 1 of 2

Slide 1 of 2

Slide 1 of 2

Slide 1 of 2

Slide 1 of 2

Slide 2 of 2

Slide 2 of 2

Slide 2 of 2

Slide 2 of 2

- Congruent triangles sss sas asa aas
- 4-4 proving triangles congruent asa aas
- Triangle congruence asa and aas
- What is included side
- 4-3 proving triangles congruent sss sas
- 4-4 proving triangles congruent-sss sas answers
- 4-4 proving triangles congruent-sss, sas
- What is sss sas asa aas and hl
- Asa and aas difference
- Sss sas asa aas
- Sss sas asa and aas congruence
- Proving triangle congruent statements reasons
- 4-5 triangle congruence sss and sas
- 4-3 using congruent triangles
- 4-3 congruent triangles
- Aas congruence rule
- Congruent by sss
- Unit 4: congruent triangles
- Quiz 6-2 proving triangles are similar
- 5 triangle congruence theorems
- Triangle congruence review maze
- How to prove congruence
- 4-4 lesson quiz geometry
- 4-5 proving triangles congruent
- Right triangle congruence theorem
- 4 congruent triangles
- Triangle proofs reasons list
- 7-4 similar triangles sss and sas similarity
- 3 4 5 triangle
- Lesson 4-3 triangle congruence by asa and aas
- Hl congruence
- 4-6 triangle congruence asa aas and hl answers
- 4-6 triangle congruence asa aas and hl answers
- Triangle congruence asa aas and hl
- Congruence postulate
- Unit 3 lesson 4 proving angles congruent
- Proving the congruent supplements theorem
- If abc and gef are congruent by the asa criterion
- Statement and reason math
- 4-5 triangle congruence sss and sas
- 7-3 triangle similarity aa sss sas worksheet answers
- Triangle similarity aa sss sas
- Sas example geometry
- 3 4 5 triangle
- Sss sas aa
- Triangle congruence sss and sas
- 7-3 triangle similarity aa sss sas
- Triangle similarity aa sss sas
- 7-3 triangle similarity aa sss sas
- Sss or sas
- Triangle similarity: sss and sas quiz
- 4-4 congruent triangles
- 4-4 triangle congruence sss and sas
- 7-3 triangle similarity aa sss sas worksheet answers
- Solve triangle aas
- A polygon with six congruent sides and six congruent angles