Completing the Square in Circle Equation
Circle of equation : (x – h)2 + (y – k)2 = r2
Center point : (h,k)
To find the standard form of the given circle equation by factoring we can use a technique called completing the square. This will help us to quickly identify the circle’s center point (h,k) and the radius.
(Please click on the picture to see it clear)
Center Point and Radius
Keep in mind that the factored form of a circle equation reveals the center point (h,k) and the radius. In the above example, (3, -4) is the center point and the radius is the square root of 26.