Ac = ad, angle CAB= angle DAB,AB=AB∴△CAB≌△DAB.

Angle CBE= Angle DBE, CB=DB

Become again

∴△CEB≌△DEB

The second way: (in two right-angled triangles, one of the right-angled sides and the hypotenuse are equal, then the two triangles are equal)

∫ Angle B= Angle D=90? ，AB=AD，AC=AC

∴△ABC≌△ACD, ∴ angle ACB= angle ACD, that is, the certificate is obtained.

The third way: (in two right-angled triangles, one of the right-angled sides and the hypotenuse are equal, then the two triangles are equal)

∫ Angle ADB= Angle BCD=90? ，AD=BD，AB=BA

∴△ABD≌△BAC ∴AD=BC