列代数式有诀窍.可归纳为如下六点: 一、准确理解数量关系例如“a、b两数的和与a、b两数的差的积”,这里涉及到“和”、“差”、“积”三个数量关系,“和”是指a+b,“差”是指a,—b,上述“和”与“差”之间的数量关系是“积”,即列式为(a+b)(a-b).又如“比x大10％的数”,如果不正确理解数量关系,容易错成x+10％或10％x.正确答案应是(1+10％)x. Column algebraic equations can be summed up as follows: First, to accurately understand the quantitative relationship such as “a, b the sum of the two numbers and the a, b two numbers of the product of the difference,” here involves “and”, “bad”, “Product” has three quantitative relationships. “And” means a+b, “Poor” means a, and -b. The quantitative relationship between “and” and “Poor” is “product”, that is, the formula is ( a+b)(ab). Another example is “a number that is 10% larger than x”. If you do not understand the quantity relationship correctly, it is easy to mistake x+10% or 10%x. The correct answer should be (1+10%)x .