By siltation, as part of the bed load
The circle has two forms of equation - General Form and Standard Form. The general form of the equation of the circle would be x^2 + y^2 + Dx + Ey + F = 0. The constants of this equation are D , E and F. The way to use general form is to complete the square and then proceed the equation in standard form. In that way we can identify the radius and center of the given circle.
