#include <iostream>

 #include <cstdio>

 #include <cmath>

 #define eps 1e-3

 using namespace std;

 int ax,ay,bx,by,cx,cy,dx,dy;

 int r,q,p;

 inline double dis(double a,double b,double c,double d)

 {

     return sqrt(pow(a-c,)+pow(b-d,));

 }

 inline double cal(double x,double y)

 {

     double x1,y1,x2,y2,t1,t2;

     double lx=cx,ly=cy,rx=dx,ry=dy;

     while (fabs(rx-lx)>eps || fabs(ry-ly)>eps)

     {

         x1=lx+(rx-lx)/; y1=ly+(ry-ly)/;

         x2=lx+(rx-lx)/*; y2=ly+(ry-ly)/*;

         t1=dis(ax,ay,x,y)/p+dis(x,y,x1,y1)/r+dis(x1,y1,dx,dy)/q;

         t2=dis(ax,ay,x,y)/p+dis(x,y,x2,y2)/r+dis(x2,y2,dx,dy)/q;

         if (t1>t2) lx=x1,ly=y1;

         else rx=x2,ry=y2;

     }

     return dis(ax,ay,x,y)/p+dis(x,y,lx,ly)/r+dis(lx,ly,dx,dy)/q;

 }

 int main()

 {

     scanf("%d%d%d%d",&ax,&ay,&bx,&by);

     scanf("%d%d%d%d",&cx,&cy,&dx,&dy);

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

     double x1,y1,x2,y2,t1,t2;

     double lx=ax,ly=ay,rx=bx,ry=by;

     while (fabs(rx-lx)>eps || fabs(ry-ly)>eps)

     {

         x1=lx+(rx-lx)/;  y1=ly+(ry-ly)/;

         x2=lx+(rx-lx)/*; y2=ly+(ry-ly)/*;

         t1=cal(x1,y1); t2=cal(x2,y2);

         if (t1>t2) lx=x1,ly=y1;

         else rx=x2,ry=y2;

     }

     printf("%.2lf\n",cal(lx,ly));

     return ;

 }