c、d是线段ab上两点,d是ac的中点,cb=4cm,db=7cm,求ab、ac的长快来啊

问题描述:

c、d是线段ab上两点,d是ac的中点,cb=4cm,db=7cm,求ab、ac的长
快来啊

ab=ac+cb=6+4=10cm
ac=ad+dc
=cd+dc
=2dc
=2(db-cb)
=2(7-4)
=6(cm)

ab=10cm,ac=6cm.
a_3cm_d_3cm_c_4cm_b

cd=db-cb=7-4=3
ac=2cd=2*3=6cm
ab=ac+cb=6+4=10cm