在证明线段成比例时,较常用的方法是证明两三角形相似.对于初学者来说,一时难以确定哪两个三角形相似.本文介绍一种确定两三角形相似的通用方法——三点定位法. 三点定位法,就是从求证的四条成比例的线段中,确定两组 When proving the proportion of line segments, the more common method is to prove that the two triangles are similar. For beginners, it is difficult to determine which two triangles are similar. This article describes a general method to determine the similarity of two triangles—three-point positioning method. The three-point positioning method is to determine two groups from the four probable line segments