在初一的一节数学课上,笔者出示了这样一道题:有一块长是5m,宽是3m的长方形草坪(如图1).现欲从中开辟出一条小路,小路水平方向的宽度恒为1m,求剩下草坪的面积是多少?学生中出现了两种解法:图1%解法一因为小路水平方向的宽度恒为1m,所以如果把小路右边的草坪向左移动1m,那么左右两边的草坪可以合并为一块长为4m,宽为3m的长方形(如图2),所以剩下 In the first day of a math class, the author presented such a question: There is a long 5m, 3m wide rectangular lawn (Figure 1). Now want to open up a path, the horizontal width of the path of constant 1m, seek the area of ​​the rest of the lawn is how many? There are two solutions to students: Figure 1% Solution Because the width of the road is always constant width of 1m, so if the lawn to the left of the path to move 1m left and right Lawn can be merged into a rectangle 4m long and 3m wide (Figure 2), so the rest