#include<iostream>

 #include<cstdio>

 #include<cstring>

 #include<algorithm>

 #include<cmath>

 #define int long long

 #define rep(i,s,e) for(register int i=s;i<=e;++i)

 #define dwn(i,s,e) for(register int i=s;i>=e;--i)

 using namespace std;

 inline int read()

 {

     int x=,f=;

     char c=getchar();

     while(c<''||c>'') {if(c=='-') f=-; c=getchar();}

     while(c>=''&&c<='') {x=x*+c-''; c=getchar();}

     return f*x;

 }

 inline void write(int x)

 {

     if(x<) {putchar('-'); x=-x;}

     if(x>) write(x/);

     putchar(x%+'');

 }

 struct node

 {

     double x,y;

 }a,b,c,d;

 double p,q,r;

 inline node calc_point(node a,node b,double k)

 {

     node point;

     point.x=(b.x-a.x)*k+a.x;

     point.y=(b.y-a.y)*k+a.y;

     return point;

 }

 inline double calc_dis(node a,node b)

 {

     return sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));

 }

 inline double check_two(double k1,double k2)

 {

     node point_one=calc_point(a,b,k1),point_two=calc_point(c,d,k2);

     double dis1=calc_dis(a,point_one)/p,dis2=calc_dis(point_one,point_two)/r,dis3=calc_dis(point_two,d)/q;

     return dis1+dis2+dis3;

 }

 inline double check_one(double k)

 {

     double l2=0.0,r2=1.0;

     while(r2-l2>1e-)

     {

         double mid12=l2+(r2-l2)/3.0,mid22=r2-(r2-l2)/3.0;

         if(check_two(k,mid12)>check_two(k,mid22)) l2=mid12;

         else r2=mid22;

     }

     return check_two(k,l2);

 }

 signed main()

 {

     scanf("%lf%lf%lf%lf",&a.x,&a.y,&b.x,&b.y);

     scanf("%lf%lf%lf%lf",&c.x,&c.y,&d.x,&d.y);

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

     double l1=0.0,r1=1.0;

     while(r1-l1>1e-)

     {

         double mid11=l1+(r1-l1)/3.0,mid21=r1-(r1-l1)/3.0;

         if(check_one(mid11)>check_one(mid21)) l1=mid11;

         else r1=mid21;

     }

     printf("%.2lf",check_one(l1));

     return ;

 }