Suzhou ac hotel lounge

∵ The rectangle is folded along a straight line AC, and the point B falls on the point E,

∴∠BAC=∠EAC,AE=AB=CD，

Opposite sides of rectangular ABCD AB CD,

∴∠DCA=∠BAC，

∴∠EAC=∠DCA，

Let AE and CD intersect at f, then AF=CF,

∴AE-AF=CD-CF，

That is DF=EF,

∴DFFC=EFAF，

And ≈AFC =≈EFD,

∴△ACF∽△EDF，

∴DFFC=DEAC=35，

Let DF=3x and FC=5x, then AF=5x,

In Rt△ADF, AD=AF2? DF2=(5x)2？ (3x)2=4x，

∫AB = CD = DF+FC = 3x+5x = 8x，

∴ADAB=4x8x= 12.

So the answer is: 12.