#include <bits/stdc++.h>
using namespace std;
inline long long mod(long long n, long long m) {
  long long ret = n % m;
  if (ret < 0) ret += m;
  return ret;
}
long long gcd(long long a, long long b) {
  return (b == 0LL ? a : gcd(b, a % b));
}
long long exp(long long a, long long b, long long m) {
  if (b == 0LL) return 1LL;
  if (b == 1LL) return mod(a, m);
  long long k = mod(exp(a, b / 2, m), m);
  if (b & 1LL) {
    return mod(a * mod(k * k, m), m);
  } else
    return mod(k * k, m);
}
const long long N = 100100;
long long n;
const double EPS = 1e-14;
pair<double, double> solve(long long x[], long long vx[], long long x1,
                           long long x2) {
  double l = 0.0, r = 1e9;
  for (long long i = 1; i <= n; i++) {
    if (vx[i] == 0) {
      if (x[i] <= x1 or x[i] >= x2) {
        cout << -1 << "\n";
        exit(0);
      }
      continue;
    }
    double cur1 = (x2 - EPS - x[i]) / vx[i];
    double cur2 = (x1 + EPS - x[i]) / vx[i];
    if (cur1 < cur2) swap(cur1, cur2);
    l = max(l, cur2);
    r = min(r, cur1);
  }
  if (l > r) {
    cout << -1 << "\n";
    exit(0);
  }
  return pair<double, double>(l, r);
}
long long x[N], y[N], vx[N], vy[N];
int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  cin >> n;
  long long x1, asdgas, x2, y2;
  cin >> x1 >> asdgas >> x2 >> y2;
  if (x1 == x2 or asdgas == y2) {
    cout << -1 << "\n";
    return 0;
  }
  for (long long i = 1; i <= n; i++) {
    cin >> x[i] >> y[i] >> vx[i] >> vy[i];
  }
  pair<double, double> a1 = solve(x, vx, x1, x2);
  pair<double, double> a2 = solve(y, vy, asdgas, y2);
  double l = max(a1.first, a2.first);
  if (l > a1.second + EPS or l > a2.second + EPS) {
    cout << -1 << "\n";
    return 0;
  }
  cout << setprecision(10) << fixed;
  cout << l << "\n";
  return 0;
}
