The radius is the distance from the center to any point. The distance from (2,1) to (0,1) is of course 2. The general formula for a circle with radius r and center (a,b) is

In our case we get
Answer:
Step-by-step explanation:
x-11
Answer:
I'd say none, as we're missing something in this problem. Make sure you've included everything to solve this problem. Thanks.