It is known that, as shown in the figure, square ABCD, e, m, F and N are the points on ad, AB, BC and CD respectively. If EF ⊥ Mn, we prove that EF = Mn

It is known that, as shown in the figure, square ABCD, e, m, F and N are the points on ad, AB, BC and CD respectively. If EF ⊥ Mn, we prove that EF = Mn

It is proved that: as shown in the figure, the crossing point E is eg ⊥ BC at g, the crossing point m is MH ⊥ CD at h, the∵ quadrilateral ABCD is a square, ∵ eg = MH, eg ⊥ MH, ∵ EF ⊥ Mn, ∵ 2 + ⊥ 3 = 90 degree, ∵ 1 = ∵ 2, ∵ in △ EFG and △ MNH, ∵ 1 = ∵ 2EG = MH ⊥ EGF = ∵ MHN = 90 degree, ∵ ef