如图所示,已知三角形ABC中,AB=AC,F在AC上,在BA的延长线上取AE=AF,求证：EF⊥BC.

如图所示,已知三角形ABC中,AB=AC,F在AC上,在BA的延长线上取AE=AF,求证：EF⊥BC. 如图所示,已知△ABC中,AB=AC,F在AC上,在BA延长线上取AE=AF,求证:EF⊥BC 如图所示,已知三角形ABC中,AB＝AC,F在AC上,在BA的延长得线上取AE＝AF,求证EF垂直BC 已知三角形ABC中AB=AC,F在AC上,在BA延长线上取AE=AF,求证:EF垂直BC 如图,已知三角形ABC中,AB=AC,F在AC上,在BA的延长线上截取AE=AF,求证BD垂直于BC 如图,已知三角形ABC中,AB=AC,在BA延长线上取AE=AF,求证：EF垂直于BC 如图,在△ABC中,AB=AC,在BA的延长线上取一点E,在AC上取一点F,使AE＝AF.求证：EF⊥BC 如图,三角形ABC中,AB=AC,在BA的延长线上取AE=AF,求证EF垂直BC 已知：如图△ABC中,AB=AC,在BA的延长线上及AC边上分别截取AE=AF.求证：EF ⊥ BC 如图,已知△ABC中,AB-AC,F在AC上,在BA的延长线上截取AE=AF,求证ED垂直BC. 在三角形ABC中 AB=AC E在CA的延长线上 F在AB上 且AE=AF 求证EF垂直BC 如图,△ABC中,AB=AC,在BA的延长线上取AE=AF,求证：EF⊥BC