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

void solve() {
    int a, b;
    cin >> a >> b;
    pii p[4];
    for (int i = 1; i <= 3; ++i) cin >> p[i].x >> p[i].y;
    int 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);
    pii 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';
    int l1 = fabs(p[1].x - D.x) + fabs(p[1].y - D.y);
    int 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 = double(l1) / a, t2 = double(l2) / b;
    if (b * l1 == a * l2) printf("%.12f\n", t1 + (fabs(D.x - p[3].x) + fabs(D.y - p[3].y)) / b);
    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) printf("%.12f\n", s / a);
        else printf("%.12f\n", t2 + dt + (s - ds) / b);
    }
    else {
        double dl = l1 - t2 * a;
        double dt = dl / (a + b);
        double ds = s - (t2 + dt) * a;
        printf("%.12f\n", t2 + dt + ds / b);
    }
}

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