#include <bits/stdc++.h>
using namespace std;
int main() {
  int t;
  scanf("%d", &t);
  while (t--) {
    int N;
    scanf("%d", &N);
    vector<int> a(N + 1);
    vector<int> b(N + 1);
    int sum = 0;
    for (int i = 1; i <= N; ++i) {
      scanf("%d", &a[i]);
      sum += a[i];
      b[i] = a[i];
    }
    if (sum % N != 0) {
      printf("-1\n");
      continue;
    }
    vector<vector<int>> ans;
    for (int i = 2; i <= N; ++i) {
      if (a[i] % i == 0) {
        b[i] -= a[i];
        b[1] += a[i];
        ans.push_back({i, 1, a[i] / i});
      } else {
        int m = i - a[i] % i;
        b[1] -= m;
        b[i] += m;
        ans.push_back({1, i, m});
        ans.push_back({i, 1, (a[i] + m) / i});
        b[i] -= (a[i] + m);
        b[1] += (a[i] + m);
      }
    }
    for (int i = 2; i <= N; ++i) {
      b[1] -= sum / N;
      b[i] += sum / N;
      ans.push_back({1, i, sum / N});
    }
    printf("%d\n", (int)ans.size());
    for (vector<int>& v : ans) {
      printf("%d %d %d\n", v[0], v[1], v[2]);
    }
  }
}
