I last holiday.
A:went swimming
B:go swimming
C:went swiming
如图,在Rt△ABC中,∠C=90°,AD是△ABC的角平分线,DC=3,则点D到AB的距离是( )
“a=12”是“直线l1:(a+2)x+(a﹣2)y=1与直线l2:(a﹣2)x+(3a﹣4)y=2相互垂直”的( )