a, \(\widehat{B}\) =2.\(\widehat{C}\)
=> \(\widehat{DBA}\) = \(\widehat{C}\)
=> 180 độ - \(\widehat{DBA}\) = 180 độ - \(\widehat{C}\)
=> \(\widehat{ABE}\) = \(\widehat{ACK}\) (đccm)
b, xét ΔACK và EBA ta có:
AC = BE
CK = AB
\(\widehat{ABE}\) = \(\widehat{ACK}\)
=> ΔACK = ΔEBA
=> AK = AE (đpcm)