As shown in the figure, B is the point on the line ad, C is the midpoint of the line BD, ad = 10, BC = 3 cd.ab The length of /___________________________ / a b c d

As shown in the figure, B is the point on the line ad, C is the midpoint of the line BD, ad = 10, BC = 3 cd.ab The length of /___________________________ / a b c d

cd=bc=3
ab=ad-bc-cd=10-3-3=4