题目(2016年湖州中考题)如图1,在等腰△ABC中,BC=7,AB=AC=4,在底边BC上取一点D,连结AD,使得∠DAC=∠ACD.将△ACD沿着AD所在直线折叠,使得点C落在点E处,AE与BC交于点M,连结BE,得到四边形ABED,则BE的长是() The subject (2016 Huzhou test questions) as shown in Figure 1, in the isosceles △ ABC, BC = 7, AB = AC = 4, take a point D on the bottom BC, connecting AD, so ∠ DAC = ∠ ACD. △ The ACD is folded along the line where AD is located so that point C falls at point E, AE intersects BC at point M, joins BE to obtain a tetragonal ABED, then the length of BE is ()