What is the radius of a circle whose equation

- What is the radius of a circle whose equation is x2+y2+8x−6y+21=0
- What is the radius of a circle whose equation is (x+5)^2+(y-3)^2=4^2
- What is the radius of a circle whose equation is x2+y2−10x+6y+18=0
- What is the radius of a circle whose equation is (x-7)2+(y-10)2=4
- What is the radius of a circle equation
- What is the radius of a circle whose equation is x 7 2
- What is the radius of a circle whose equation is x 7
- What is the radius of a circle whose equation is x2
- What is the radius of a circle whose equation is x^2+y^2