2004年全国各地的中考数学试卷中几乎都考到了知识点——一元二次方程根的判别式、根与系数的关系.但考查的角度、解决问题的方法并不相同,归纳起来大致有这么几类: 一、由‘知识点’列方程组或不等式组解 In 2004, almost all of the mathematics examination papers in the middle school across the country were tested on the knowledge point: the relationship between the discriminant and the root and coefficient of the quadratic equation root. However, the examination angle and the solution to the problem are not the same. Several categories: First, by the ’knowledge point’ list equations or inequalities group solution