Given: DB bisects AE <D = <B Prove: AD = BE AB C D E Given Definition of Bisector Vertical Angle Theorem ?? DB bisects AE DC = CB <ACD = <ECB ? ΔACD =

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Given: DB bisects AE <D = <B Prove: AD = BE AB C D E Given Definition of Bisector Vertical Angle Theorem ?? DB bisects AE DC = CB <ACD = <ECB ? ΔACD = ΔECBAD = BE Why is this wrong and fix it. Fill in missing reason. Fill in missing statement.

Given: DB bisects AE <D = <B Prove: AD = BE AB C D E Given Definition of Bisector Vertical Angle Theorem AAS postulateCPCTC DB bisects AE AC = CE <ACD = <ECB <D = <B ΔACD = ΔECBAD = BE Why is this wrong and fix it. Fill in missing reason. Fill in missing statement. AE gets cut in half not DB Other given is seen above Explain by marking on picture CPCTC always used to prove a part is congruent after proving congruent triangles A S A ANSWER KEY

Given: <D & <B are right angles <DAE = <BEA Prove: AD = BE AB D E Given CPCTC ? ? <D & <B are right angles <D = <B AE = AE ? ΔADE = ΔEBAAD = BE Why is this wrong and fix it. Fill in missing reason. Fill in missing statement. Definition of Right Angle

Given: <D & <B are right angles <DAE = <BEA Prove: AD = BE AB D E Given CPCTC AAS Reflexive Property <D & <B are right angles <D = <B AE = AE <DAE = <BEA ΔADE = ΔEBAAD = BE Why is this wrong and fix it. Fill in missing reason. Fill in missing statement. Right Angle Theorem ANSWER KEY A S A Other given is seen above Using a shared piece. It is a theorem not a definition. Def of Right Angle = right angle is 90 Explain by marking on picture

Congruent Triangle Proof Oral Test Rubric Congruent Triangle Proof Oral Test Student correctly completed 1 items in proof. Each item was correctly & clearly explained. Student correctly completed 2 items. However explanatio ns were not clear or only partially correct. Student correctly completed 2 items in proof. Each item was correctly & clearly explained. Student correctly completed 3 items. However explanatio ns were not clear or only partially correct. Student correctly completed 3 items in proof. Each item was correctly & clearly explained. Student correctly completed all 4 items. However explanatio ns were not clear or only partially correct. Student correctly completed all 4 items including filling in 3 missing items & correcting error in proof. Each item was correctly & clearly explained.