美夢成真教甄討論區

請問老師以下如何解題呢？謝謝

由內分比定理
CE / AE = BC / BA = 1 / 2
AC = 9，CE = 3

EF / BF = CE / CB = 1 / 2

FG / BC = EF / EB = 1 / 3
FG = 2