如图,点A.B.C.D是直线l上顺次四点,M.N分别是AB.CD的中点若MN=a,BC=b求AD的长

问题描述:

如图,点A.B.C.D是直线l上顺次四点,M.N分别是AB.CD的中点若MN=a,BC=b求AD的长

MB + CN = a - b
AD = 2(MB + CN) + BC = 2a -b要过程!好,再详细点。MB + CN = MN - BC = a - bAD = AM + MB + BC + CN + ND因为AM = MB, CN = ND所以AD = 2(MB + CN) + BC = 2a -b