Triangle ABC and ace are equilateral triangles. ① prove: DC = be. ② prove: OA is the angle bisector of ∠ doe
(1) It is proved that ∵ abd and △ AEC are equilateral triangles, ∵ ad = AB, AE = AC, ≌ DAB = ≌ CAE = 60 °, ≌ DAC = ≌ BEC, ≌ be = DC. (2) because ≌ abd and ≌ ace are equilateral triangles, ad = AB, AC = AE, angle DAB = angle C
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