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khanhphuhv
2 năm trước
Cho tam giác ABC cân tại A. Kẻ BE,CK là các đường cao của tam giác ABC (E thuộc AC, K thuộc AB). a, CMR: a, AEK là tam giác cân b,CMR:EK//BC c,Nếu BK=KE=EC thì tam giác ABC là tam giác gì? Làm giúp mk câu b mk làm đc câu a rồi
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