#include <bits/stdc++.h>
#define pdd pair<double, double>
#define x first
#define y second
#define int long long
#define esp 1e-7
using namespace std;

void solve() {
    double a, b;
    cin >> a >> b;
    pdd p[4];
    for (int i = 1; i <= 3; ++i) cin >> p[i].x >> p[i].y;
    double l = min(p[1].x, p[2].x), r = max(p[1].x, p[2].x), d = min(p[1].y, p[2].y), u = max(p[1].y, p[2].y);
    pdd D = {max(l, min(r, p[3].x)), max(d, min(u, p[3].y))}; // AB构成矩形 内 离C哈密顿距离最近的点
    //cout << D.x << ' ' << D.y << '\n';
    double l1 = fabs(p[1].x - D.x) + fabs(p[1].y - D.y);
    double l2 = fabs(p[2].x - D.x) + fabs(p[2].y - D.y);
    double s = fabs(p[1].x - p[3].x) + fabs(p[1].y - p[3].y);
    double t1 = l1 / a, t2 = l2 / b;
    if (fabs(t1 - t2) <= esp) cout << t1 + (fabs(D.x - p[3].x) + fabs(D.y - p[3].y)) / b << '\n';
    else if (t1 < t2) {
        double xa, dx = (t2 - t1) * a;
        double dt = dx / (b - a);
        dx += a * dt;
        double ds = l1 + dx;
        if (ds > s) cout << s / a << '\n';
        else cout << t2 + dt + (s - ds) / b << '\n';
    }
    else {
        double dl = l1 - t2 * a;
        double dt = dl / (a + b);
        double ds = s - (t2 + dt) * a;
        cout << t2 + dt + ds / b << '\n';
    }
}

signed main() {
    ios::sync_with_stdio(false), cin.tie(nullptr);
    int t = 1;
    cin >> t;
    while (t--) solve();
}