实际问题中的变量关系,可以考虑用方程思想,建立不等式,也可构造不等式,运用不等式的性质去分析、转化问题,使问题获得解决.解不等式的应用问题关键是建立教学模型.利用数学模型解应用题必须要过好三关,走好四步.解答应用题的关键在于审题上,而要准确理解题意,又必须过好三关:(1)事理关:通过阅读、理 The relationship between variables in practical problems can be considered by using equations, establishing inequalities, constructing inequalities, and using the nature of inequalities to analyze and transform problems and solve the problems. The key to the application of solution inequalities is to establish teaching models and to use mathematical models. The solution to the problem must be a good three, take a good four steps. The key to answering the problem lies in the trial, and to accurately understand the meaning of the problem, but also must pass three levels: (1) Affairs: Through reading, management