问题:
圆x 2+y 2-ax+2=0与直线l相切于点A(3,1),则直线l的方程为( ) A.2x-y-5=0
B.x-2y-1=0
C.x-y-2=0
D.x+y-4=0
圆x 2+y 2-ax+2=0与直线l相切于点A(3,1),则直线l的方程为( ) A.2x-y-5=0
B.x-2y-1=0
C.x-y-2=0
D.x+y-4=0
B.x-2y-1=0
C.x-y-2=0
D.x+y-4=0
参考答案: