计算: ( − 6 ) − ( + 4 ) = .
-6÷×= .
-的相反数是 .
-的倒数是 .
如图所示,在Rt△ABC中,∠C=90°,∠ABC的平分线BD交AC于D,若CD=3,则点D到AB的距离是( )
如图所示,△ABC中,AB = AC,AD = AE,∠BAD = 20°,则∠EDC = °.