Ecuacion segundo grado POO C++

/* Antonio Villanueva Segura
 * Calculo Ecuacion 2° grado estilo POO c++
 *Para test puedes emplear ....
 *http://es.onlinemschool.com/math/assistance/equation/quadratic/
*/
#include <iostream>
#include <cmath>
using namespace std;

class Ecuacion{
    public:
    Ecuacion(double a=3,double b=60,double c=1);//Constructor con parametros por defecto
    void run();//Calculo ecuacion 2° grado

    private:
    double a,b,c;
    double det(double a,double b, double c);//Calculo determinante
};
/**********************************************************************/
Ecuacion::Ecuacion(double a,double b,double c) :a(a),b(b),c(c){}
/**********************************************************************/
double Ecuacion::det(double a,double b, double c){return (b*b)-(4*a*c);}
/**********************************************************************/
void Ecuacion::run (){//Calculo ecuacion 2° grado
    double d=det(a,b,c);//Calcula determinante

    if (d<0){//Solucion Imaginaria i
        cout<<-b/(2*a)<<" + "<<sqrtf(abs(d))/(2*a)<<" i" <<endl;
        cout<<-b/(2*a)<<" - "<<sqrtf(abs(d))/(2*a)<<" i "<<endl;
    }
    else{//Solucion Real
        cout<< ((-b)+ sqrtf(d) ) / (2*a) <<endl;
        cout<< ((-b)-sqrtf(d)) /(2*a) <<endl;
    }
}
/**********************************************************************/
/**********************************************************************/
int main (){

    Ecuacion ecuacion;
    ecuacion.run();//Emplea parametro por defeto a=3 b=60 c=1

    //Calculo raices imaginarias a=1 , b=-2, c=5
    Ecuacion ecuacion2(1,-2,5);
    ecuacion2.run();

    return 0;
}