我们都遇到过这样一个问题:“画一条直线,把图1的面积两等分.”教师在教学中一般可引导学生得出三种方案(如图2).A N C D E FM B O a b%图2c实际上,根据图2中的直线a、b、c,还可进一步得出结论:各种方案下都可画出许多直线,如将直线a绕MN的中点O旋转,只要与边AF、BC都相交,则仍可平分面积.于是可以 We have encountered such a problem: “Draw a straight line, the area of ​​Figure 1, two equal. ” Teachers in teaching can generally guide students to come up with three options (Figure 2) .ANCDE FM BO ab% Figure 2c In fact, based on the straight lines a, b and c in Figure 2, we can further conclude that many straight lines can be drawn under various schemes, such as rotating the line a around the midpoint O of MN, AF, BC are intersect, you can still split the area