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I don’t know how to do the proofs. Need answers.

I don’t know how to do the proofs. Need answers.-example-1
User Opsidao
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1 Answer

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The prove, ∠ BCF ≅ ∠ DCF. is achieved using Angle addition postulate

How to complete the proof

The two column proof is written as follows

Statement Reason

AE ⊥ FC given

∠ A ≅ ∠ E given

∠ B ≅ ∠ D given

AC ≅ CE definition of midpoint

Δ BAC ≅ Δ DEC AAS congruence theorem

∠ BCA ≅ ∠ DCE CPCTC

∠ ACF ≅ ∠ DCF right angles are equal

∠ ACF = ∠ BCA +∠ BCF Angle addition postulate

∠ DCF = ∠ DCE +∠ DCF Angle addition postulate

∠ DCE +∠ DCF = ∠ BCA +∠ BCF Substitution

∠ BCA +∠ DCF = ∠ BCA +∠ BCF Substitution

∠ DCF = ∠ BCF Simplifying

User Mehdi Nellen
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