S
susu.ken


Cho tam giac deu ABC. Tu mot diem m thuoc mien trong cua tam giac ta dung tia Mx//BC cat AB tai D, dung tia My//AC cat BC tai E, tia Mz//AB tai F.
a/ Xac dinh dang cac tu giac ADMF,BDME,CFME
b/CMR:goc DMe=goc EMF=goc FMD
c/CM: chu vi DEF> 1/2 chu vi ABC
a/ Xac dinh dang cac tu giac ADMF,BDME,CFME
b/CMR:goc DMe=goc EMF=goc FMD
c/CM: chu vi DEF> 1/2 chu vi ABC