The document discusses the standard form of a circle equation and provides examples of writing the equation of various circles given their center and radius. It begins by defining the components of a circle - the center (h,k) and radius r. Then it shows the standard form of a circle equation: (x-h)2 + (y-k)2 = r2. The rest of the document provides the center and radius of several circles and has the reader write out the corresponding standard equation for each one.