同学们在列方程解应用题时,有时发现得到的解答不合理或与正确答案不符.检查解方程的过程,又没有发现任何计算错误.毛病出在哪里呢?这可能是所列的方程不正确.那么怎样判断所列方程正确或不正确呢? 如果所列方程是正确的,那么它必须同时满足四个条件: (1) 方程两边意义相同; When classmates solve problems in the equations, they sometimes find that the answers are unreasonable or inconsistent with the correct answer. Check the process of solving equations, and did not find any calculation errors. Where is the problem? This may be the listed equation is not Correct. So how do you judge whether the listed equation is correct or incorrect? If the listed equation is correct, then it must satisfy four conditions at the same time: (1) Both sides of the equation have the same meaning;