线段的和差倍分在初中数学中时常出现,是以“全等三角形的对应边相等”为基础,结合有关图形的性质,具有较强的综合性;通常添加辅助线将问题转化为两线段相等。对于特殊图形也可利用面积或相似三角形的性质等方法来解决。一、线段和差型(a+b=c)的解决策略1.延长线段a(或b)形成一条长为a+b的线段d,将问题转化为d=c;2.在线段c上截取线段a(或b)形成一条长为c-a(或c-b)的 The sum of difference between segments is often found in junior math mathematics. It is based on the equivalence of congruent triangles of congruent triangles and combines with the nature of graphics. It is usually integrated with auxiliary lines to convert the problem into Two segments equal. For special graphics can also use the area or the nature of similar triangles and other methods to solve. First, the line segment and differential (a + b = c) to solve the strategy 1. To extend the line segment a (or b) to form a line length a + b d, the problem is converted to d = c; 2. On the line c Intercept line a (or b) to form a length of ca (or cb)