As shown in the figure, it is known that a, B and C are on the same straight line, ab = 24cm, BC = 38ab, e is the midpoint of AC, D is the midpoint of AB, find the length of de

As shown in the figure, it is known that a, B and C are on the same straight line, ab = 24cm, BC = 38ab, e is the midpoint of AC, D is the midpoint of AB, find the length of de

∵ AB = 24cm, BC = 38ab, ∵ BC = 9, ∵ AC = AB + BC = 33, ∵ e is the midpoint of AC, D is the midpoint of AB, ∵ AE = 12ac = 332, ad = 12ab = 12, ∵ de = ae-ad = 92