Răspunsuri

2014-04-22T07:06:30+03:00
ED//BC⇒< EDB≡<DBC (alt. interne congruente)
< EBD≡< DBC, din aceste doua relatii ⇒<EBD≡< EDB⇒ΔBED isoscel⇒ED≡EB
AB≡AC⇒EB≡DC⇒ED≡DC
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