The General Form of an Equation of a Circle The To convert an equation in general form to standard form square form of an equation of a circle is x y Cx Dy E 0 Complete the square for the x and y terms Group together the x terms x 4x y Determine what value needs to be added to both sides of the equation to complete the square x 4x 4 y 8y 16 10 4 16 10 Factor the polynomials x y 4x 8y 10 0 1 T 10 h k 2 10 2 41 the 2 4 2 2 20 y