题目

如图，在▱ABCD中，E是AB的中点，EC交BD于点F，则△BEF与△DCB的面积比为（ ）A. B. C. D. 答案：【答案】D【解析】根据平行四边形的性质得出AB=CD，AB∥CD，根据相似三角形的判定得出△BEF∽△DCF，根据相似三角形的性质和三角形面积公式求出即可．解：∵四边形ABCD是平行四边形，E为AB的中点，∴AB=DC=2BE，AB∥CD，∴△BEF∽△DCF，∴==，∴DF=2BF，=()2=，∴=，∴S△BEF=S△DCF，S△DCB=S△DCF，∴==，故选： ________ the moment they heard the starting signal given by the teacher. A. Ran the children down the hill B. Down the hill did the children run C. Down the hill the children ran D. Down the hill ran the children