Proving Congruent Triangles

• Identifying Corresponding sides and angles of shapes

Postulates that Prove Congruent Triangles

• Hypotenuse Leg Theorem
  • method to prove right triangles are congruent
• Side Side Side Postulate (SSS)
• Side Angle Side Postulate (SAS)
• Angle Side Angle Postulate (ASA)
• Angle Angle Side(AAS)

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Once we have congruence- CPCTC


Corresponding Parts of Congruent Triangles are Congruent (CPCTC)

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• Practice Proofs
• Proof Problem (A proof with errors, can you find them?)

What about the others like SSA or ASS?

• AAA (Angle Angle Angle) Does not prove that two triangles are congruent. However, it does make two triangles similar.
• What about Side Side Angle (SSA).
  • This does not make two triangles congruent. Why SSA (Side Side Angle) does not make two triangles congruent.

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Other Types of Proof
• Coordinate Geometry Proofs
• Isosceles Triangle Proofs
• Indirect proof