(1)∵△AEF~△CBF, AE:ED=1:3, ∴AE:BC=1:4
△AEF的面积:△CBF的面积=1:16
(2)△ABF=(1/5)△ABC
四边形EFCD=△ACD﹣△AEF=△ABC﹣(1/5)△ABE
=△ABC﹣(1/5)(1/4)△ACD
=(19/20) △ABC
∴△ABF:四边形EFCD=(1/5)△ABC:(19/20)△ABC
=4:19
[img] http://i812.photobucket.com/albums/zz42/mingyangtw/3254_zps211302d6.jpg [/img]
请问这答案有错吗?