设:E(x,y),C(m,n),则:
AB=(3,3)、CB=(1-m,4-n)
因为AB=(1/2)CB,则:
(3,3)=(1/2)(1-m,4-n)
得:1-m=6、4-n=6
得:m=-5、n=-2
C(-5,-2)
CE=(x+5,y+2)、ED=(4-x,-3-y)
因CE=-(1/4)ED,则:
-4CE=ED
-4(x+5,y+2)=-(4-x,-3-y)=(x-4,y+3)
-4(x+5)=x-4、-4(y+2)=y+3
得:x=-16/5,y=-11/5
即:E(-16/5,-11/5)