折叠是一种对称变换,具有变换前后两部分图形全等等重要性质.求折叠中的线段长,近年来成为各地中考的一个“热点”.解决此类问题,需要综合运用平行四边形、全等三角形(以及等腰三角形、直角三角形)的性质与判定,还要运用分类讨论的方法.下面,我们来看几个例子. Folding is a kind of symmetric transformation, with the transformation of the two parts before the completion of the graphics and other important properties of the nature. Seeking the length of the line in the fold in recent years has become a “hot spot ” to solve these problems.To solve these problems, the need to comprehensive use of parallelograms, The nature and determination of congruent triangles (and isosceles triangles, right triangles), as well as the methods used to categorize them, are discussed below. Here are a few examples.