用解析法证几何题,表面上是高中解析几何的内容,但对于有些平几问题,巧用初中已学的两点间的距离公式,两直线位置关系,函数关系式等知识,往往可以迅速而准确地获得证明.这种问题的解题关键是,选择适当的坐标系,确定已知的定点坐标和动点坐标,将题设的几何条件转化为代数等式,再用解析方法推出结论. Analytical forensic geometry problem, the surface is the content of high school analytic geometry, but for some problems, skillfully use junior high school has learned the distance between two points formula, the relationship between the two linear relationship, the relationship between function and other knowledge can often quickly And accurately get the proof.The key of solving this kind of problem is to select the appropriate coordinate system, determine the known fixed point coordinates and moving point coordinates, the geometry of the problem is converted to algebraic equation, and then draw conclusions .