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Monday ­ Jan. 2, 2012

Welcome Back!!! Hope you had a restful break :)

* Discuss 4.4/4.5 on Triangle Congruence Postulates

­ Watch Video Example­ Do some examples of each­ Assign practice problems/proofs 

       for tomorrow.

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Proving Triangles Congruent:

SSS

SAS

ASA

AAS

HL

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Example 1:Use SSS to explain why ∆ABC ≅ ∆DBC.

Section 4.4

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Example 4:Use SAS to explain why ∆ABC ≅ ∆DBC.

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Example 5:Show that the triangles are congruent for the given value of the variable.∆MNO ≅ ∆PQR, when x = 5.

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Example 6:Given: BC ║ AD, BC ≅ ADProve: ∆ABD ≅ ∆CDB

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Example 7: Given: QP bisects ∠RQS. QR ≅ QSProve: ∆RQP ≅ ∆SQP

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Example 2:Determine if you can use ASA to prove ∆NKL ≅ ∆LMN. Explain.

Section 4.5

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Example 4: Use AAS to prove the triangles congruent.Given: JL bisects ∠KLM, ∠K ≅ ∠MProve: ∆JKL ≅ ∆JML

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Example 5: Determine if you can use the HL Congruence Theorem to prove the triangles congruent. If not, tell what else you need to know.

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Example 6: Determine if you can use the HL Congruence Theorem to prove ∆ABC ≅ ∆DCB. If not, tell what else you need to know.

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Homework:

Finish Pink THEOREM SHEET

Attachments

Congruent Triangles Video