The equation is y^2+x^2=16 for the basic circle, so 4) is eliminated. Then, it goes down 1 y-unit and right 2 x-units, so 2) is eliminated as well. The reason 3 is wrong is because in an equation, when you add to the x then it goes left, and when you subtract from y it goes up. That means that only number 1 is a viable solution
Option 1. Radius is square root of 16 which is 4. (x-2)^2, when set to zero means move right 2. (y+1)^2, means move center down 1. So the center should be (2,-1).
