题目

某人站在河边能看到对岸岸边一棵树的完整像,人从岸边后退6米时,恰好还能看见整棵树的像,再往后退,就看不见完整像了.已知此人身高1.5米,河岸高出水面1米,河宽40米,求河对岸这棵树有多高?

提问时间：2021-03-24

答案

9米,具体要画图不是很好说-_-!
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简单的说一下,最左边表示人,1.5米,右边为树和影子,连接一下和水面有个交点,利用相似三角形可以算出交点离岸边为4米,影子就是9米,很简单的：）