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(2008•咸宁)如图,在Rt△ABC中,AB=AC.D,E是斜边BC上两点,且...
(2008•咸宁)如图,在Rt△ABC中,AB=AC.D,E是斜边BC上两点,且∠DAE=45°,将△ADC绕点A顺时针旋转90°后,得到△AFB,连接EF,下列结论:①△AED≌△AEF;②△ABE∽△ACD;③BE+DC=DE;④BE
2+DC
2=DE
2.其中正确的是( )
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A.②④
B.①④
C.②③
D.①③
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