二次函数是描述现实世界变量之间以及某些单变量最优化问题的重要数学模型．中考通常通过创设丰富的实际情景,将二次函数问题融入到具体的实际问题中,考查同学们利用二次函数解决最优化问题或其他实际问题的能力,中考试卷中的这类问题往往是由课本中的一些题目变形而来,本文以北师大版教材《数学》九年级下册第二章第7节中的题目为例,向同学们介绍这类问题的共性和解法． Quadratic functions are important mathematical models that describe real-world variables and some univariate optimization problems. The entrance exam usually involves the creation of rich practical scenarios to incorporate quadratic function problems into concrete practical problems and examine the ability of students to use quadratic functions to solve optimization problems or other practical problems. Such problems in the examination papers are often caused by Some of the problems in textbooks have been transformed. This paper uses the subjects in the second grade of the second grade of the 9th grade mathematics book “Mathematics” as an example to introduce students to the commonalities and solutions to these problems.