同学们已学过因式分解,并已学会运用有关知识解决实际问题．在日常生活中,同学们还要善于发现与这些知识有关的问题,培养自己化实际问题为数学问题的能力．下面举例说明． The students have learned factorization and have learned to use relevant knowledge to solve practical problems. In daily life, students must also be good at finding problems related to these knowledge, and cultivate their ability to turn practical problems into mathematical problems. Here is an example.