Question

[linh nguyen]

cho tam giac ABC vuong tai A, co duong phan giac BD. Ke DE vuong goc voi BC (E ϵ BC) . tren tia doi cua tia AB lay diem F sao cho AF = CE

chung minh a, ΔABD=ΔEBD

b, BD la duong trung trung truc cua doan thang AE

c, AD < DC

d, goc ADF= goc EDC va E,D,F thang hang

Answer 1

[Bùi Công Gia Bảo]