性质如图1正6//BC,过A点作三直线交旦子于E、F、G三点,交刀C于B、D、C三点.若F为EG的中,奴,则D必为BC中点. C承。 B证明产酬所以又所以 因为EF EF//刀D·FAAD.A刀// EF,联想图1,延长BA交FE的延长线于G,此时则必有EF一五工子.这样可将它FZ~八E·旦了转化成EF·EG一月丑·且二,再 The nature is shown in Figure 1 positive 6 / / BC, over A points for three straight lines in the E, F, G three points, the knife C in B, D, C three points. If F is EG, the slave, D Must be BC midpoint. C Cheng. B proves that the paycheck is so because EF EF// knife D·FAAD.A knife // EF, Lenovo chart 1, to extend BA to the extension line of FE to G, then there must be EF five workers. Convert it FZ~E E.Den into EF·EG January ugly and II, again