#include <bits/stdc++.h>
using namespace std;
double a, b, c, x, y, d, e, f;
double av, av2, ev1, ev2, an, an2;
double m1, m2, m3;
bool ch(double m) {
  double t1, t2;
  if (m >= b)
    t1 = m - b, t2 = b;
  else
    t2 = m, t1 = 0;
  ev1 = (c * t2) + (e * t1);
  ev2 = (d * t2) + (f * t1);
  an = av + ev1;
  an2 = av2 + ev2;
  m1 = sqrt(an * an + an2 * an2);
  if (m1 / m <= a) return 1;
  return 0;
}
double bs() {
  double f = 0, l = 4e9, m, s = 200;
  while (s--) {
    m = (f + l) / 2;
    if (ch(m))
      l = m;
    else
      f = m;
  }
  return m;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  double x1, y1;
  cin >> x >> y >> x1 >> y1;
  cin >> a >> b;
  cin >> c >> d;
  cin >> e >> f;
  av = x - x1;
  av2 = y - y1;
  cout << fixed << setprecision(7) << bs();
  return 0;
}
