#include <iostream>
#include <cstdio>
#include <cstring>
#include <vector>
#include <string>
#include <algorithm>
#include <queue>
#include <set>
#include <map>
#include <cmath>
using namespace std;
typedef long long LL;
#define REP(_,a,b) for(int _ = (a); _ <= (b); _++)
const double eps = 1e-10;
const double P = 0.99;//退火速度
const int dirX[9] = {0,1,-1,1,-1,0,0,1,-1};
const int dirY[9] = {0,1,-1,-1,1,1,-1,0,0};
double a,b,c,d,e,f;
int dcmp(double x) {
    if(fabs(x) < eps) return 0;
    else if(x < 0) return -1;
    else return 1;
}
bool getRoot(double a,double b,double c,double &x1) {
    double delta = b*b-4*a*c;
    if(dcmp(delta) < 0) return false;
    x1 = (-b+sqrt(delta))/(a*2);
    return  true;
}
void solve() {

    double step = 0.1;
    double x = 0, y = 0;
    double ans = 1/c;
    while(step > eps) {
        int dir = 0;
        REP(i,1,8) {
            double xx = x + step*dirX[i]*1.0;
            double yy = y + step*dirY[i]*1.0;
            double zz;
            if(getRoot(c,d*yy+e*xx,a*xx*xx+b*yy*yy+f*xx*yy-1,zz)) {
                if(xx*xx+yy*yy+zz*zz < ans) {
                    dir = i;
                    ans = xx*xx+yy*yy+zz*zz;
                }
            }
        }
        if(dir != 0) {
            x += step*dirX[dir];
            y += step*dirY[dir];
        }
        step *= P;
    }
    printf("%.8lf\n",sqrt(ans));
}
int main(){

    while(~scanf("%lf%lf%lf%lf%lf%lf",&a,&b,&c,&d,&e,&f)) {
        solve();
    }
    return 0;
}