解题几何是数形结合的典型范例 ,它是通过坐标系的建立 ,将几何问题转化为代数问题来处理 ,反过来 ,很多代数问题利用解析几何理论 ,可转化为几何问题来处理 .本文结合例题介绍几种常用的解析几何模型 ,供学习时参考 .1　距离模型例 1　已知ｘ ,ｙ∈Ｒ ,且ｘ2 + ｙ2 =2 ,求ｘ2 Problem solving geometry is a typical example of the combination of numbers and shapes. It is established through the establishment of coordinate systems, and the geometric problems are transformed into algebraic problems. In turn, many algebraic problems use analytical geometry theory and can be transformed into geometric problems. The example describes several commonly used analytical geometry models for reference when learning. 1 Distance Model Example 1 Known x, y∈R, and x2 + y2 =2, find x2