#include <iostream>
#include <math.h> 


using namespace std;

int main() {

    // Forma directa
    cout<<"x1 " <<  (-(-1)+sqrt((-1)*(-1)-4*1*(-12)))/(2*1) << endl;
    cout<<"x2 " <<  (-(-1)-sqrt((-1)*(-1)-4*1*(-12)))/(2*1) << endl;


    // Usando variables
    double a = 1.0;
    double b = 4.0;
    double c = 1.0 ;   
    cout<<"x1 " <<  (-b+sqrt(b*b-4.0*a*c))/(2.0*a) << endl;
    cout<<"x2 " <<  (-b-sqrt(b*b-4.0*a*c))/(2.0*a) << endl;
}