是不是;;求△DCE的面积与△ABD的面积比=?
∵四边形ABCD是梯形,AB//DC,对角线AC,BD交于点E,S△DCE∶S△CEB= 1:3
∴ S△DCB∶S△DCE= 4∶1
S△ADE=S△CEB=3S△DCE,
∴S△ABE∶S△ABD=3∶4
S△ADE∶S△ABD=1∶4
∴S△DCE∶S△ABD
=﹙S△CEB/3﹚∶﹙4S△ADE﹚
=﹙S△CEB/3﹚∶﹙4S△CEB﹚
=1∶12
是不是;;求△DCE的面积与△ABD的面积比=?
∵四边形ABCD是梯形,AB//DC,对角线AC,BD交于点E,S△DCE∶S△CEB= 1:3
∴ S△DCB∶S△DCE= 4∶1
S△ADE=S△CEB=3S△DCE,
∴S△ABE∶S△ABD=3∶4
S△ADE∶S△ABD=1∶4
∴S△DCE∶S△ABD
=﹙S△CEB/3﹚∶﹙4S△ADE﹚
=﹙S△CEB/3﹚∶﹙4S△CEB﹚
=1∶12