晨mu
幼苗
共回答了23个问题采纳率:95.7% 举报
因为CD = 2/3AC,
所以CD < AC.
所以有两种情况(点D不可能在CA延长线上):
1.当D在线段AC上时,
AD = AC - CD = (1 - 2/3)AC
即,1/3AC = 6
AC = 18
AB = 1/2AC = 9
CD = 2/3AC = 12
2.当D在AC的延长线上时,
AD = AC + CD = (1+ 2/3)AC
即,5/3AC = 6
AC = 18/5
AB = 1/2AC = 9/5
CD = 2/3AC = 12/5
1年前
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