#include <bits/stdc++.h>

using namespace std;

#define X first

#define Y second

typedef long long ll;

typedef double db;

typedef pair<db,db> P;

const db eps=1e-;

P A,B,C,D,L,R;db p,q,r;

void read(P &t){scanf("%lf%lf",&t.X,&t.Y);}

db dist(P a,P b){return sqrt((a.X-b.X)*(a.X-b.X)+(a.Y-b.Y)*(a.Y-b.Y));}

db check(db rat)

{

    R=P(C.X+(D.X-C.X)*rat,C.Y+(D.Y-C.Y)*rat);

    return dist(R,D)/q+dist(L,R)/r;

}

db solve(db rat)

{

    L=P(A.X+(B.X-A.X)*rat,A.Y+(B.Y-A.Y)*rat);

    db l=,r=;

    while(fabs(l-r)>eps)

    {

        db lm=l+(r-l)/3.0,rm=r-(r-l)/3.0;

        if(check(lm)<check(rm)) r=rm; else l=lm;

    }

    return dist(A,L)/p+check((l+r)/2.0);

}

int main()

{

    read(A);read(B);read(C);read(D);

    scanf("%lf%lf%lf",&p,&q,&r);

    db l=,r=;

    while(fabs(l-r)>eps)

    {

        db lm=l+(r-l)/3.0,rm=r-(r-l)/3.0;

        if(solve(lm)<solve(rm)) r=rm; else l=lm;

    }

    printf("%.2lf",solve((l+r)/2.0));

    return ;

}