纵观近几年全国各省市的中考试题 ,求平面几何图形中函数关系式的问题 ,已成为中考命题的热点之一。解这类问题 ,须以几何图形为背景 ,根据几何图形有关的性质 ,正确建立几何元素间的等量关系 ,方能确定函数与自变量之间的函数关系式。现结合近几年部分省市的中考题 ,探讨其解法 ,供初三同学复习时参考 Looking at the examination questions in various provinces and cities across the country in recent years, the issue of function relations in plane geometrical figures has become one of the hot spots in the examination proposition. To solve this kind of problem, we must use the geometry as the background, according to the nature of the geometry, the correct establishment of the geometric relationship between the geometric elements, can only determine the functional relationship between the function and the independent variables. This is a combination of the examination questions of some provinces and cities in recent years to discuss its solution for the reference of junior high school students for review.