如图,已知E F两点把线段AB分成2:3:4,D是线段AB的中点,FB=24,【1】求DF的长【2】AE:ED是多少

问题描述:

如图,已知E F两点把线段AB分成2:3:4,D是线段AB的中点,FB=24,【1】求DF的长【2】AE:ED是多少

,_______,______,____,______________,A E D F B 设AE为2X,EF为3X,FB为4X,AB为9X (1) 4X=24 X=6 所以:DF=0.5AB—FB =4.5X—4X =0.5X =3 (2) AE:DE=2X:(3X—0.5X) =2:2.5