—Oh, really? I ____________. I _____________ go and visit him.
A:didn't know; am going to
B:hadn't known; would
C:haven't known; will
D:didn't know; will
小明在计算一个二项式的平方时,得到的正确结果是4x2+12xy+■,但最后一项不慎被污染了,这一项应是( )
如图,在△ABC和△DCB中,AC与BD交于点E,且AC=BD,AB=CD.(1)求证:△ABC≌△DCB;(2)若∠AEB=70°,求∠EBC的度数.
下列计算正确的是( )