18．如图.在梯形中......求的长． [解析] 解法一: 如图1.分别过点作于点. 于点．································ 1分．又. 四边形——青夏教育精英家教网—

18．如图.在梯形中......求的长． [解析] 解法一: 如图1.分别过点作于点. 于点．································ 1分．又. 四边形是矩形．．································· 2分 ... ．． . ························································································· 4分在中.. ．··············································· 5分解法二: 如图2.过点作.分别交于点．····························· 1分 . ． . ．在中.... ···································································· 2分在中.... ．．····················································································· 4分在中.. ．···························································· 5分 [点评] 统观北京及全国各地中考试卷.几何中的计算往往会与两个知识点有关:①圆,②梯形. 本题考点:等腰直角三角形的性质.特殊四边形的性质.勾股定理. 难度系数:0.6. 【查看更多】

题目列表(包括答案和解析)

(本小题满分8分)

如图，在梯形ABCD中，DC∥AB，AD=BC， BD平分∠ABC，∠A=60°，过点D作DE⊥AB，过点C作CF⊥BD，垂足分别为E、F，连接EF，求证：△DEF为等边三角形。

查看答案和解析>>

(本小题满分7分)

⑴解不等式组：

⑵如图所示，在梯形ABCD中，BC∥AD，AB=DC，点M是AD的中点．