1 . 【问题初探】:(1)如图①,在
中,点
、
分别在边
、
上,连接
,
∥
,
.若
,则
的长为______;
【问题深入】:(2)如图②,在扇形
中,点
是
上一动点,连接
,
,
,
,求四边形
的面积的最大值;
【拓展应用】:(3)为进一步促进西安市文化和旅游高质量发展,推动全市文明旅游创建工作,结合
年陕西省文明旅游示范单位申报工作,一并开展
年西安市文明旅游示范单位评选工作
某地为参加评选积极改善环境,拟建一个四边形休闲广场
,其大致示意图如图③所示,其中
∥
,
米.点
处设立一个自动售货机,点
是
的中点,连接
,
,
与
交于点
,连接
,沿
修建一条石子小路(宽度不计),将
和
进行绿化.根据设计要求,
.为倡导绿色新风尚,现要使绿化的面积尽可能的大,请问
和
的面积之和是否存在最大值?若存在,请求出
和
面积之和的最大值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50196d293a863fe2f9e46199052ab8c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a19338598965bb3856cdd0236bbf694.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
【问题深入】:(2)如图②,在扇形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4819c39c281427826e1b3f7a4c2b720.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16d65cecaf8a3dc2953f4109c75a981e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ff5c21185c13eae675906dabd3593c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9774f83067ed956a551bc41adcce0469.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ea16ceca816f7d3d50650af141baf42.png)
【拓展应用】:(3)为进一步促进西安市文化和旅游高质量发展,推动全市文明旅游创建工作,结合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e946baf1316ac1f219398ecedadf6cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e946baf1316ac1f219398ecedadf6cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e1d0f65817ba32a732040518f41440.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5b697b4b6230d62b428fce3c27571ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db54223bb3fc2fe2497213a4d1f94827.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db54223bb3fc2fe2497213a4d1f94827.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fc963e25d03b5c552bc063e44835364.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/376ca8f6e81ccd6846145ada511c4749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3df364013269114330c0eff2d2c65a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fc963e25d03b5c552bc063e44835364.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/376ca8f6e81ccd6846145ada511c4749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fc963e25d03b5c552bc063e44835364.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/376ca8f6e81ccd6846145ada511c4749.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/20/d921fc65-dd48-4845-9c40-6be8a69c71c7.png?resizew=589)
您最近一年使用:0次
2 . (1)特殊发现
如图1,正方形BEFG与正方形ABCD的顶点B重合,BE、BG分别在BC、BA边上,连接DF,则有:①
;②直线DF与直线AG所夹的锐角等于 度;
(2)理解运用
将图1中的正方形BEFG绕点B逆时针旋转,连接DF、AG,
①如图2,(1)中的结论是否仍然成立?请说明理由;
②如图3,若D、F、G三点在同一直线上,且过AB边的中点O,BE=4,直接写出 AB的长
(3)拓展延伸
如图3,点P是正方形ABCD的AB边上一动点(不与A、B重合),连接PC,沿PC将△PBC翻折到△PEC的位置,连接DE并延长,与CP的延长线交于点F,连接AF, 若PA=3PB,则
的值是否是定值?请说明理由.
如图1,正方形BEFG与正方形ABCD的顶点B重合,BE、BG分别在BC、BA边上,连接DF,则有:①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9589155dce30e6352476d7f7aa52b1b8.png)
(2)理解运用
将图1中的正方形BEFG绕点B逆时针旋转,连接DF、AG,
①如图2,(1)中的结论是否仍然成立?请说明理由;
②如图3,若D、F、G三点在同一直线上,且过AB边的中点O,BE=4,直接写出 AB的长
(3)拓展延伸
如图3,点P是正方形ABCD的AB边上一动点(不与A、B重合),连接PC,沿PC将△PBC翻折到△PEC的位置,连接DE并延长,与CP的延长线交于点F,连接AF, 若PA=3PB,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f2a52b6ada8397ba27df60dac471a0c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/14/4b4c7cf5-b4b1-42a3-9d5f-92fccd5aba6c.png?resizew=840)
您最近一年使用:0次
3 . 问题背景
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/27/37b7c1a1-a626-4db4-8a00-b2790a8e2a8b.png?resizew=570)
(1)如图1,已知
,求证:
;
(2)尝试应用
如图2,在
和
中,
,
,
与
相交于点F,点D在
边上,
,求
的值;
(3)拓展创新
如图3,D是
内一点,过点A作
的垂线,过点D作
的垂线,两垂线交于点M,连接
,
,
,
,
,
,求
的长.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/27/37b7c1a1-a626-4db4-8a00-b2790a8e2a8b.png?resizew=570)
(1)如图1,已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67061e6fa526d1e082bed7b01c819982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aa98026a648010decfaf672dc9141c9.png)
(2)尝试应用
如图2,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26813466e2ee49a493881a4384fc8748.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b4ed3163605f3c832ff52779a12f507.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49ff78516ae61f74de69fd93920535c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08341fa8b1827c032f796e5f88941b78.png)
(3)拓展创新
如图3,D是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05e42166b2ec2def11ceff10557eadd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78701c5e569550504c07bd3d617cc3f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a20cb14fea4a7cad4b7775a3dd67df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e1f4f255d191786f7d330d278868c2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
您最近一年使用:0次
2022-12-25更新
|
63次组卷
|
2卷引用:陕西省汉中市略阳县2021-2022学年九年级上学期期中考试数学试卷
4 . 【基础巩固】
(1)如图1,△ABC∽△ADE,求证:△ABD∽△ACE;
【尝试应用】
(2)如图2,在平行四边形ABCD中,点E,F分别在BC,AC上,△AEF∽△ACD,BE=2,CE=6,求AF•AC的值.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/038c0dd9-27ff-43a4-ba83-e5201992049d.png?resizew=515)
【拓展提高】
(3)如图3,在(2)的条件下,连接DF,AB=AF,已知cos∠ACD=
,求tan∠ACB的值.
(1)如图1,△ABC∽△ADE,求证:△ABD∽△ACE;
【尝试应用】
(2)如图2,在平行四边形ABCD中,点E,F分别在BC,AC上,△AEF∽△ACD,BE=2,CE=6,求AF•AC的值.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/038c0dd9-27ff-43a4-ba83-e5201992049d.png?resizew=515)
【拓展提高】
(3)如图3,在(2)的条件下,连接DF,AB=AF,已知cos∠ACD=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d266a04f3dc7483eddbc26c5e487db.png)
您最近一年使用:0次
2021-11-20更新
|
190次组卷
|
2卷引用:陕西省宝鸡市2023-2024学年九年级上学期期中模拟数学试题
名校
5 . (1)问题背景:如图(1),已知
,求证:
;
(2)尝试应用:如图(2),在
和
中,
,
,
与
相交于点F.点D在
边上,
,求
的值;
(3)拓展创新:如图(3),D是
内一点,
,
,
,
,则
的长为________.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67061e6fa526d1e082bed7b01c819982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aa98026a648010decfaf672dc9141c9.png)
(2)尝试应用:如图(2),在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26813466e2ee49a493881a4384fc8748.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/150eee7c63ba236fa91505cd69770134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c8980c6ea83710640bf9bea7f054274.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08341fa8b1827c032f796e5f88941b78.png)
(3)拓展创新:如图(3),D是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36395a1f890888bae8c6b1cfb95e8d68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/587458141d890533c0c32aa249a27ad0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54275b7e571660d0a9e0370fbfe5050b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33c99fc553ecb3e2afdb7058201bc642.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/7/a70af434-7694-4a28-8f62-79d2daa505ea.png?resizew=465)
您最近一年使用:0次
2021-10-21更新
|
250次组卷
|
2卷引用:陕西省西安市师大附中2021-2022学年九年级上学期第一次月考数学试卷
解题方法
6 . 小波在复习相似三角形一章时,温故后进行了操作与拓展.请帮助他解决以下问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/5/9f7aeac1-3484-4598-8203-b4f9be6fd896.png?resizew=474)
(1)小波想作出一个内接于
最大正方形.如图1,在
中,
边上的高为4.他先在边
上任取了一点
,作出正方形
,使
在
边上,
在
内,请你在
及其内部,以点B为位似中心作正方形
的位似正方形
,且使正方形
的面积最大(不要求写作法).
(2)求(1)中作出的正方形
的边长.
(3)在(2)的条件下,在射线
上截取
,连接
(如图2).当
时,猜想
的度数,并尝试证明.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/5/9f7aeac1-3484-4598-8203-b4f9be6fd896.png?resizew=474)
(1)小波想作出一个内接于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e76d226471eae8c4cb7d1fafe95b0e81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6f8906c9d7ce68defb89848faa531ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ca9581c221aa3016b035444015a7e6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16d2bdb1b10b98c3cb9e6ebaa8a1f2c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca72786ed0499924472614baada4ec01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ca9581c221aa3016b035444015a7e6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ac79e422ba4876949f0514c44539b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ac79e422ba4876949f0514c44539b1.png)
(2)求(1)中作出的正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ac79e422ba4876949f0514c44539b1.png)
(3)在(2)的条件下,在射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7785afeeaf274892253d04b4f693b367.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7df7c43dd51ecde238a068b8138e8b7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/201e51551d1eb5b1e92b6faf85dc4714.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe2395cf9c7b05f0c9475b3a7130ace1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2002cc14d6d6c1a8d3cd7225b4b2e211.png)
您最近一年使用:0次
名校
7 . (1)问题初探:在直角三角形中,两直角边的长度之和是10,当两直角边的长分别是_____,_____时,直角三角形的面积最大;
(2)问题解决:如图,在一个
的内部作一个矩形
,其中点A和点D分别在两直角边上,
在斜边上,
,矩形面积最大是多少?在解决这个问题时,有一位爱动脑筋的同学通过作辅助线进行了转化,如图①,过点D作
.所以
,又因为四边形
是矩形,所以
于是
,那么求矩形
的面积最大,就可以转化为求平行四边形
的面积最大,设平行四边形
的边
,平行四边形
的面积为
,请你按这个思路继续完成这问题:
(3)问题拓展:如图②,矩形
中,
,点E是
边上的动点(点E与
两点不重合),连接
,点F是
边上的动点,过F作![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
交
于G,求
面积最大值.
(2)问题解决:如图,在一个
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80eff52574ec119d2f52fa165da837ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/209156e05cbe7e7307bce3aa31e04beb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/799aa99b791d43c5bd9dc43cd5078f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e84d68d15ab90c52e54d5ff42cdddb73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/969840741beedd25288a5ee4c9775a09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08ea9ef4a5db6c65316d90ed2a9ed038.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7398082f10073da5bfa37fd4c758af2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7398082f10073da5bfa37fd4c758af2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cd99679fe64a8fa1020b7fcb1db9a8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7398082f10073da5bfa37fd4c758af2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be8b9cb83196b47c32b7eb0efe380ef1.png)
(3)问题拓展:如图②,矩形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bea885bde24022c1c4a319f697f6e64a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80934ff67b4ceeaa13b00c029db565dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ed3797a759dca7272c4f8a2434423ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91c168d3d9ebbaa9a5563ff5cfc8c4d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e5e61804ce550636a0354e0a78a22d.png)
![](https://img.xkw.com/dksih/QBM/2021/12/18/2874943327092736/2876792555356160/STEM/722f8bd9-a583-4f6e-8733-bbcc389199a0.png?resizew=395)
您最近一年使用:0次
2021-12-20更新
|
273次组卷
|
3卷引用:陕西省西安交通大学附属中学分校2021-2022学年九年级上学期12月月考数学试题
解题方法
8 . 【探索发现】
如图①,是一张直角三角形纸片,
,小明想从中剪出一个以
为内角且面积最大的矩形,经过多次操作发现,当沿着中位线
、
剪下时,所得的矩形的面积最大,随后,他通过证明验证了其正确性,并得出:矩形的最大面积与原三角形面积的比值为_____________.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/14/0a6edc03-20a6-4782-bf8a-440e71402725.jpg?resizew=531)
【拓展应用】
如图②,在
中,
,
边上的高
,矩形
的顶点
、
分别在边
、
上,顶点
、
在边
上,则矩形
面积的最大值为_________.(用含
的代数式表示)
【灵活应用】
如图③,有一块“缺角矩形”
,
,
,
,
,小明从中剪出了一个面积最大的矩形(
为所剪出矩形的内角),求该矩形的面积.
【实际应用】
如图④,现有一块四边形的木板余料
,经测量
,
,
,且
,
,木匠徐师傅从这块余料中裁出了顶点
、
在边
上且面积最大的矩形
,求该矩形的面积.
如图①,是一张直角三角形纸片,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60d9142db4dd2ef151bf3d4a63afb61e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/febc9a89d0d1c97b88c0f4acd32b4e67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/14/0a6edc03-20a6-4782-bf8a-440e71402725.jpg?resizew=531)
【拓展应用】
如图②,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e781a2489271bfd1597cba1bb6f5887.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61d22f065ec04de109d913e8e7855110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ac79e422ba4876949f0514c44539b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ac79e422ba4876949f0514c44539b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec707e3852297341490f121f2c4a245b.png)
【灵活应用】
如图③,有一块“缺角矩形”
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c0fbd6bf34420df721e0abf6a9d3dc7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3da16fe2e1ce327bcc7a83495338e735.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdc832ac10c407e12e59f434799f5fff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6f75e575cbfaea176d9fc9a019c0426.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/febc9a89d0d1c97b88c0f4acd32b4e67.png)
【实际应用】
如图④,现有一块四边形的木板余料
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a42eb49692bc89261738fd0c85e4d17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6350669a3c0efd71a739c98bf4267e3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91c2c65b91be7fe27bfb15642448f0a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e071479287e774f7f0990b1a649658f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/383839a3cbbb8a97941b6a40d6d340ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ac79e422ba4876949f0514c44539b1.png)
您最近一年使用:0次
名校
9 . 在一平面内,线段
,线段
,将这四条线段顺次首尾相接,把
固定,让
绕点A从
开始逆时针旋转角
到某一位置时,
将会跟随出现到相应的位置.
![](https://img.xkw.com/dksih/QBM/2021/10/19/2832606455578624/2833231993085952/STEM/e8c63a79-f569-4f7f-b6c1-575ca72b5a7d.png)
(1)论证:如图1,当
时,设
与
交于点O,求证:
;
(2)发现:如图2,a继续旋转,取线段
的中点M,当点M与点B距离最大时,求点M到
的距离;
(3)拓展:当点C在
下方,且
与
垂直时,
与
交点为O.请直接 写出
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4630b9ca3d20635161fa8fbf812b9128.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0560a05e574a42ae68097a5a69b0a7d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d34e595767a4d8597b8d973af489a71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/481e426224c3a3ce9bb5a731eed81c40.png)
![](https://img.xkw.com/dksih/QBM/2021/10/19/2832606455578624/2833231993085952/STEM/e8c63a79-f569-4f7f-b6c1-575ca72b5a7d.png)
(1)论证:如图1,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/936fe43fddabaf910c0419a146372b37.png)
(2)发现:如图2,a继续旋转,取线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(3)拓展:当点C在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c298dddcf8f4b5ff038c480314f72320.png)
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名校
10 . 【阅读理解】如图1,在平面直角坐标系中,直线
的函数关系式
,
、
是直线
上任意两个不同的点,过点
、
分别作
轴、
轴的平行线交于点
,则线段![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58e480a3daf0c0895a6f0ec0d13db8b6.png)
,于是有
,即
的值仅与
的值有关,不妨设
为直线
:
的“纵横比”.
【直接应用】(1)直线
的“纵横比”为________,直线
的“纵横比”为________.
【拓展提升】(2)如图2,已知直线
:
与直线
:
互相垂直,请用“纵横比”原理及相关的几何知识分析
与
的关系,并加以证明.
【综合应用】(3)如图3,已知
,
是
轴上一动点,线段
绕着点
按逆时针方向旋转
至线段
,设此时点
的运动轨迹为直线
,若另一条直线
,且与
有且只有一个公共点,试确定直线
的函数关系式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c15fb18163df0690365a0d2e7ee88f5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b225d772013d021cf1bfe7b9421fa5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6b7e35faab6d74fa0c36599c39d1698.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58e480a3daf0c0895a6f0ec0d13db8b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51329afd390da4bb48fd1641273f1c7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/757409ee3fddfe6cf9650bd619021c4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/906fd531546e7c498bac0a94d71157d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b9274a780e98bef27600d88e1c8c070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c15fb18163df0690365a0d2e7ee88f5a.png)
【直接应用】(1)直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa6342e0a5a8942cfb1cf535ceb2c50d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85bdbaee1c6d92b27ceac6e066cfce36.png)
【拓展提升】(2)如图2,已知直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a04e8115f9314064d606037b4e6a3c0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13dea1bd3d0dd84b8b6f6ff634c5600c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0bf09159f22d26882cb1f048d4a2767.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
【综合应用】(3)如图3,已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ba33de35567ff6f8c15e7e0d37aa590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0eb26a220ed44c446105df7caa0f1063.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9268d474f8ced282134e183008268d06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/26/27b0c47e-5dd0-436e-90db-578ea5130dac.png?resizew=413)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/26/b09b4022-5434-4d77-8a65-fcbad284ff5d.png?resizew=173)
您最近一年使用:0次
2020-12-08更新
|
298次组卷
|
2卷引用:陕西省西安市碑林区铁一中学2020-2021学年九年级上学期期中数学试题