/*
    路线可以分为三部分：在AB上的，CD上的，还有在平面上的。
    可以三分AB上的断点和CD上的断点。 
*/
#include<iostream>
#include<cstdio>
#include<cmath>
#define eps 1e-9
using namespace std;
double ax,ay,bx,by,cx,cy,dx,dy,P,Q,R,ans;
double calc(double x1,double y1,double x2,double y2){
    return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
}
double sa2(double x,double y){//CD无斜率
    double m1,m2,k,t1,t2,l,r;
    l=min(cy,dy),r=max(cy,dy);
    while(l+eps<r){
        m1=(2*l+r)/3,m2=(l+2*r)/3;
        t1=calc(cx,m1,dx,dy)/Q+calc(cx,m1,x,y)/R;
        t2=calc(cx,m2,dx,dy)/Q+calc(cx,m2,x,y)/R;
        if(t1<t2) r=m2;
        else l=m1;
    }
    t1=calc(cx,l,dx,dy)/Q+calc(cx,l,x,y)/R;
    return t1;
}
double sanfen2(double x,double y){//CD有斜率
    if(cx==dx) return sa2(x,y);
    double m1,m2,k,t1,t2,l,r,b;
    l=min(cx,dx),r=max(cx,dx);
    k=(cy-dy)/(cx-dx);
    b=cy-k*cx;
    while(l+eps<r){
        m1=(2*l+r)/3,m2=(l+2*r)/3;
        t1=calc(m1,m1*k+b,dx,dy)/Q+calc(m1,m1*k+b,x,y)/R;
        t2=calc(m2,m2*k+b,dx,dy)/Q+calc(m2,m2*k+b,x,y)/R;
        if(t1<t2) r=m2;
        else l=m1;
    }
    t1=calc(l,l*k+b,dx,dy)/Q+calc(l,l*k+b,x,y)/R;
    return t1;
}
void sanfen1(){//AB有斜率
    double m1,m2,k,t1,t2,l,r,b;
    l=min(ax,bx),r=max(ax,bx);
    k=(ay-by)/(ax-bx);
    b=ay-k*ax;
    while(l+eps<r){
        m1=(2*l+r)/3,m2=(l+2*r)/3;
        t1=sanfen2(m1,k*m1+b)+calc(m1,m1*k+b,ax,ay)/P;
        t2=sanfen2(m2,m2*k+b)+calc(m2,m2*k+b,ax,ay)/P;
        if(t1<t2) r=m2;
        else l=m1;
    }
    t1=sanfen2(l,l*k+b)+calc(l,l*k+b,ax,ay)/P;
    ans=min(ans,t1);
}
void sa1(){//AB无斜率.
    double m1,m2,k,t1,t2,l,r;
    l=min(ay,by),r=max(ay,by);
    while(l+eps<r){
        m1=(2*l+r)/3,m2=(l+2*r)/3;
        t1=sanfen2(ax,m1)+calc(ax,m1,ax,ay)/P;
        t2=sanfen2(ax,m2)+calc(ax,m2,ax,ay)/P;
        if(t1<t2) r=m2;
        else l=m1;
    }
    t1=sanfen2(ax,l)+calc(ax,l,ax,ay)/P;
    ans=min(ans,t1);
}
int main(){
    cin>>ax>>ay>>bx>>by>>cx>>cy>>dx>>dy;
    cin>>P>>Q>>R;
    ans=calc(ax,ay,dx,dy)/R;
    if(ax!=bx) sanfen1();
    else sa1();
    printf("%.2lf",ans);
    return 0;
}