题目

如图，在 △ABC 中， AB 的垂直平分线分别交 AB 、 BC 于点 D 、 E ，连接 AE ，若 AE ＝ 4， EC ＝ 2，则 BC 的长是（ ） A． 2 B． 4 C． 6 D． 8 答案：C【分析】 根据线段的垂直平分线的性质得到 EB ＝ EA ＝ 4，结合图形计算，得到答案． 【详解】 解： ∵DE 是 AB 的垂直平分线， AE ＝ 4， ∴EB ＝ EA ＝ 4， ∴BC ＝ EB ＋ EC ＝ 4＋ 2 ＝ 6 ， 故选： C ． 【点睛】 本题考查的是线段的垂直平分线的性质，解题的关键是掌握线段的垂直平分线上的点到线 把与图片相对应的描述的序号填到图下的横线上A.  John is a boy. He is of medium height with short curly hair. He is wearing a green T-shirt,dark green pants and blue shoes. B. Sarah is my aunt. She is fifty-five. She is heavy with glasses. She has short black hair. She is wearing an orange dress.  C. Nancy is good-looking.  She  has  short curly black hair. She is wearing a beautiful yellow dress and orange shoes.  D. Bruce is a doctor. He is of medium build. He has short hair and he wears small glasses. He's wearing a brown and white sweater and blue pants.  E. Jim is my friend. He's tall and thin with straight brownhair. He is wearing a white shirt, black pants and blue  shoes.            1 ._____                  2 ._____                3 ._____        4 ._____                     5. _____