Question

following the figures show that angle AOB=angle DOC




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Answer 1

Answer:

Adding (1) and (2), we get

∠AOB + ∠BOC + (∠COE + ∠DOE) + ∠AOD = 180° + 180°

⇒ ∠AOB + ∠BOC + ∠COD + ∠DOA = 360° (∠COE + ∠DOE = ∠COD)