同学们都知道,三角形的中线可将原三角形分成面积相等的两个三角形.如图1,AD是△ABC的中线,则有S△ABD=S△ADC=1/2S△ABC,利用这个性质,可以巧妙地求出一些三角形的面积.一、直接运用,紧扣性质例1如图2,在△ABC中,已知点D、E、F分别是BC、AD、CE的中点,且△ABC面积为4cm2,求阴影部分的面积. As we all know, the triangle’s middle line divides the original triangle into two triangles with the same area.As shown in Figure 1, where AD is the middle line of ABC, there is S △ ABD = S △ ADC = 1 / 2S △ ABC. , You can skillfully find the area of ​​some triangles. A direct application, closely linked to the nature of Example 1 As shown in Figure 2, △ ABC, known points D, E, F are BC, AD, CE, △ ABC area of ​​4cm2, find the shadow of the area.