#include <bits/stdc++.h>
using namespace std;
#define modulo 1000000007
#define mod(mod_x) ((((long long)mod_x+modulo))%modulo)
#define Inf 2000000005


int main(){
	
	double a,b,c,d,e,f;
	cin>>a>>b>>c>>d>>e>>f;
	
	double x = (double)c/(2.0*a);
	double y = (double)d/(2.0*b);
	x*=-1;
	y*=-1;
	double ok = y;
	double ng = 1e5;
	
	for(int i=0;i<100;i++){
		double mid = (ok+ng)/2.0;
		double v = (double)a*pow(x,2.0);
		v += (double)b * pow(mid,2.0);
		v += (double)c * x;
		v += (double)d * mid;
		v += (double)e;
		v -= (double)f;
		
		if(v<0)ok = mid;
		else ng = mid;
	}
	
	cout<<fixed<<setprecision(15)<<abs(y-ok)<<endl;
	
	return 0;
}