As shown in the figure, M is the midpoint of line AB, point C is on line AB, and AC = 6cm, n is the midpoint of AC, Mn = 4cm, find the length of line cm and ab A________ N________ C____ M_____________ B

As shown in the figure, M is the midpoint of line AB, point C is on line AB, and AC = 6cm, n is the midpoint of AC, Mn = 4cm, find the length of line cm and ab A________ N________ C____ M_____________ B

(1)CM=MN-NC
NC = an = 1 / 2 * AC = 1 / 2 * 6 = 3, Mn = 4
So cm = 4-3 = 1
(2)AB=2AM
And am = AC + cm = 6 + 1 = 7
So AB = 2 * 7 = 14