Gaokao Math Practice Question
8. 若过点 $(2,1)$ 的圆与两坐标轴都相切, 则圆心到直线 $2 x-y-3=0$ 的距离为 ( )
- A.$\frac{\sqrt{5}}{5}$
- B.$\frac{2 \sqrt{5}}{5}$
- C.$\frac{3 \sqrt{5}}{5}$
- D.$\frac{4 \sqrt{5}}{5}$
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