In order to solve the algebraic equation, where the complex polynomial has only simple zeros, one can use the simultaneous inclusion methods. The quadratic convergence condition for the Durand-Kerner simultaneous inclusion method, using point estimation theory is w^(0) \le d^(0)/(an + b), where n is the polynomial degree, d^(0) the minimum distance between the initial iterations and w^(0) is the absolute maximum of the Weierstrass factors. This paper determines the optimum quadratic convergence condition for a generalized Durand-Kerner type simultaneous inclusion method.