20 1 1 The third of 24 math problems in the senior high school entrance examination. Why are parallel lines equal in area? ! Find your own topic and explain it in detail! !
Because △ABD and △ABC have a common side AB, as long as the heights on the sides of AB are equal, the areas of these two triangles are equal. According to the distance between parallel lines, as long as point C is parallel to AB, any point on this parallel line is equal to the area of the triangle formed by AB.