定义:若一个三角形最长边是最短边的2倍,我们把这样的三角形叫做“和谐三角形”.在△ABC中,点F在边AC上,D是边BC上的一点,AB=BD,点A,D关于直线l对称,且直线l经过点F.
(1)如图1,求作点F;(用直尺和圆规作图保留作图痕迹,不写作法)
(2)如图2,△ABC是“和谐三角形”,三边长BC,AC,AB分别a,b,c,且满足下列两个条件:a≠2b,和a2+4c2=4ac+a﹣b﹣1.
①求a,b之间的等量关系;
②若AE是△ABD的中线.求证:△ACE是“和谐三角形”.
(1)如图1,求作点F;(用直尺和圆规作图保留作图痕迹,不写作法)
(2)如图2,△ABC是“和谐三角形”,三边长BC,AC,AB分别a,b,c,且满足下列两个条件:a≠2b,和a2+4c2=4ac+a﹣b﹣1.
①求a,b之间的等量关系;
②若AE是△ABD的中线.求证:△ACE是“和谐三角形”.
![](https://img.xkw.com/dksih/QBM/2021/11/26/2859401515335680/2860200258715648/STEM/69d1a098-61ec-48cc-8988-ea4702e239eb.png?resizew=472)
21-22八年级上·福建厦门·期中 查看更多[2]
福建省厦门市第五中学2021-2022学年八年级上学期期中数学试题(已下线)专题4.28 相似三角形的性质(分层练习)(基础练)-2023-2024学年九年级数学上册基础知识专项突破讲与练(北师大版)
更新时间:2021-11-27 10:35:14
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【推荐2】作图题(保留作图痕迹,不写作法)
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