共50条信息
圆\(x\)\({\,\!}^{2}+\)\(y\)\({\,\!}^{2}−2\)\(x\)\(−8\)\(y\)\(+13=0\)的圆心到直线\(ax\)\(+\)\(y\)\(−1=0\)的距离为\(1\),则\(a\)\(=(\) \()\)
进入组卷