Question

已知：以△ABC的边AB、AC、BC为边的等边三角形ABD、ACE、BCF

Answer 1

证明：∵∠ECF+∠ACF=60°∠ACB+∠ACF=60°∴∠ACB=∠ECF∵在△ECF和△ACB中∠ACB=∠ECFAC=FCBC=EC∴△FCE≌△ACB∴EF=AB∵AB=AD∴EF=AD∵∠ABD-∠ABE=∠CBE-∠ABE∴∠ABC=∠DBE∵在△ABC和△DBE中AB=BD∠ABC=∠DBEB...