阅读下面材料:
如图
,把
沿直线
平行移动线段
的长度,可以变到
的位置;
如图
,以
为轴,把
翻折
,可以变到
的位置;
如图
,以点
为中心,把
旋转
,可以变到
的位置.
像这样,其中一个三角形是由另一个三角形按平行移动、翻折、旋转等方法变成的.这种只改变位置,不改变形状大小的图形变换,叫做三角形的全等变换.
回答下列问题:
①在图
中,可以通过平行移动、翻折、旋转中的哪一种方法怎样变化,使
变到
的位置;
②指图中线段
与
之间的关系,为什么?
![](https://img.xkw.com/dksih/QBM/2018/11/3/2067681280901120/2068857207742464/STEM/10149fa145aa46478b8cc6087efd07f0.png?resizew=284)
如图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4141b26d2c32655003494a91ad6331b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fe59deb5eff9123704c5505830b597e.png)
如图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65863c1abad833b79c303bfca24f535c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93c01768cb4ced5092f9b06d5c3d63cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c2ba742a343597d9066e775ae9f88d9.png)
如图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4bb89a362c1faf4d0c306eabbb59710.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93c01768cb4ced5092f9b06d5c3d63cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93394d8a463f5ee5cbbbcb77a6771e09.png)
像这样,其中一个三角形是由另一个三角形按平行移动、翻折、旋转等方法变成的.这种只改变位置,不改变形状大小的图形变换,叫做三角形的全等变换.
回答下列问题:
①在图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e636bddc1a3d7c006ac304e96cd2551.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fa485cf3776f36aaf4abaadaf30fb85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ca13a715cae753737d1be851c132b49.png)
②指图中线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0213c5787a5a6b38d11bceca5567f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a679040c4d556723e482bacbab41356d.png)
![](https://img.xkw.com/dksih/QBM/2018/11/3/2067681280901120/2068857207742464/STEM/10149fa145aa46478b8cc6087efd07f0.png?resizew=284)
![](https://img.xkw.com/dksih/QBM/2018/11/3/2067681280901120/2068857207742464/STEM/37d9457803b248e18e710706e20c1d3d.png?resizew=115)
更新时间:2018-11-05 09:23:40
|
【知识点】 旋转综合题(几何变换)
相似题推荐
解答题-作图题
|
适中
(0.65)
【推荐1】如图,在
中,
,延长
使
,线段
绕点C顺时针旋转90°得到线段
,连结
.
![](https://img.xkw.com/dksih/QBM/2020/6/25/2492088525651968/2492336782524416/STEM/5b2a6a08-d9dd-4486-9b1d-3d2d5bf49774.png?resizew=170)
(1)依据题意补全图形;
(2)当
时,
的度数是__________;
(3)小聪通过画图、测量发现,当
是一定度数时,
.
小聪把这个猜想和同学们进行交流,通过讨论,形成了证明该猜想的几种想法:
想法1:通过观察图形可以发现,如果把梯形
补全成为正方形
,就易证
,因此易得当
是特殊值时,问题得证;
想法2:要证
,通过第(2)问,可知只需要证明
是等边三角形,通过构造平行四边形
,易证
,通过
,易证
,从而解决问题;
想法3:通过
,连结
,易证
,易得
是等腰三角形,因此当
是特殊值时,问题得证.
请你参考上面的想法,帮助小聪证明当
是一定度数时,
.(一种方法即可)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a5e0a51c9e14fb246b0ba0b231c1e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb5a4bf8028cee9396367b68ea8e6f80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db54223bb3fc2fe2497213a4d1f94827.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f71d025ca44e65f63acf5452a8c55dc.png)
![](https://img.xkw.com/dksih/QBM/2020/6/25/2492088525651968/2492336782524416/STEM/5b2a6a08-d9dd-4486-9b1d-3d2d5bf49774.png?resizew=170)
(1)依据题意补全图形;
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ac24fd8615d861c57ab41326093751f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5071953255f6434eaefeab7176372564.png)
(3)小聪通过画图、测量发现,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2f9c3b578fc0598d5ec6c79404c6cc2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/176822d1db2fd6726ec2e8ab733dfa8e.png)
小聪把这个猜想和同学们进行交流,通过讨论,形成了证明该猜想的几种想法:
想法1:通过观察图形可以发现,如果把梯形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01ff27eea7545bb06f9472f91290c54e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6335f34cc64038712c6a302c6e5ba34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5071953255f6434eaefeab7176372564.png)
想法2:要证
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/176822d1db2fd6726ec2e8ab733dfa8e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/101da161ae17652ccbe7d3f888762c2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11f18bba7cc8a77f309be6bfe17335aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/967578d2c4086aef3fda57ed4cdae5c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d939c156b5e35db2b7aec5a3571f1a69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa6627444a2cbd7bc03b61dda56d065a.png)
想法3:通过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53cd55948ba9013d8f5017e7ddbce17d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d59218cb78e59013850baaa217339661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/101da161ae17652ccbe7d3f888762c2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5071953255f6434eaefeab7176372564.png)
请你参考上面的想法,帮助小聪证明当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2f9c3b578fc0598d5ec6c79404c6cc2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/176822d1db2fd6726ec2e8ab733dfa8e.png)
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解答题-作图题
|
适中
(0.65)
【推荐2】如图,在边长为1单位长度的小正方形组成的网格中,给出了格点△ABO(顶点是网格线的交点)
(1)先将△ABO向右平移2个单位后得到△A1B1C1,再将△A1B1C1绕点C1按顺时针方向旋转90°后得到A2B2C2请在正方形网格中画出上述二次变换所得到的图案;
(2)求线段A1B1旋转到A2B2的过程中所扫过的面积.
(1)先将△ABO向右平移2个单位后得到△A1B1C1,再将△A1B1C1绕点C1按顺时针方向旋转90°后得到A2B2C2请在正方形网格中画出上述二次变换所得到的图案;
(2)求线段A1B1旋转到A2B2的过程中所扫过的面积.
![](https://img.xkw.com/dksih/QBM/2019/5/18/2206408627798016/2207013168513024/STEM/7e3806b418704043a44cc1dc98cf62e9.png?resizew=197)
您最近一年使用:0次