A:am
B:is
C:are
①如果∠1=∠2,那么根据____,可得____∥____;
②如果∠DAB+∠ABC=180°,那么根据____,可得____∥____.
③当____∥____时,根据____,得∠3=∠C.
已知|z|=1,且z5+z=1,求z.
如图,△ABC中,∠C=90°,AB垂直平分线交BC于D.若BC=8,AD=5,则AC等于____
If you don’t finish your homework, I’m afraid your mother will ________ you.