初中阶段所涉及的一元一次方程、二元一次方程(组)、一元一次不等式(组)、一元二次方程等都可以转化为相应函数的最简形式,从“数”、“形”两方面以函数的观点去研究它们:从“数”的角度看,函数的解析式可看作是关于两个变量x、y的二元方程,每一组x、y的对应值,就是相应方程的一个解.从“形”的角度看,函数图象上各点的坐标既是相应函数的对应值,也是相应方程的解; The elementary equation, the bivariate equation (group), the unary inequality (group) and the one-quadratic equation involved in the junior middle school can all be transformed into the simplest form of the corresponding function. From the “” From both the “function” point of view and from the point of view of the “number”, the analytic form of a function can be seen as a binary equation about the two variables x, y, with the correspondence of each set of x, y From the perspective of “shape ”, the coordinates of each point on the image of the function are not only the corresponding values ​​of the corresponding functions but also the solutions of the corresponding equations.