(2010?青浦区二模)如图,点D、E分别在△ABC的AB、AC边上,DE∥BC,且ADAB=13,若______

2025-03-24 14:22:42
推荐回答(1个)
回答1:

∵DE∥BC,

AD
AB
1
3

DE
BC
=
1
3

又∵
DE
a

BC
=3
a

于是
EC
=
BC
-
BE
=3
a
-