#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("unroll-loops")
using namespace std;
template <typename A>
ostream& operator<<(ostream& cout, vector<A> const& v);
template <typename A, typename B>
ostream& operator<<(ostream& cout, pair<A, B> const& p) {
  return cout << "(" << p.first << ", " << p.second << ")";
}
template <typename A>
ostream& operator<<(ostream& cout, vector<A> const& v) {
  cout << "[";
  for (int i = 0; i < v.size(); i++) {
    if (i) cout << ", ";
    cout << v[i];
  }
  return cout << "]";
}
template <typename A, typename B>
istream& operator>>(istream& cin, pair<A, B>& p) {
  cin >> p.first;
  return cin >> p.second;
}
const long long MAXN = 1e5 + 7;
void check() {
  long long n, sm = 0;
  cin >> n;
  vector<long long> a(n + 1);
  for (int i = 1; i <= n; i++) cin >> a[i], sm += a[i];
  if (sm % n) {
    cout << "-1\n";
    return;
  }
  vector<vector<long long>> ans;
  auto go = [&](long long x, long long y, long long z) {
    a[x] -= x * z;
    a[y] += x * z;
    ans.push_back({x, y, z});
  };
  for (int i = 2; i <= n; i++) {
    if (a[i] % i) go(1, i, i - a[i] % i);
    go(i, 1, a[i] / i);
  }
  for (int i = 1; i <= n; i++) {
    go(1, i, sm / n);
  }
  cout << ans.size() << "\n";
  for (vector<long long>& b : ans)
    cout << b[0] << " " << b[1] << " " << b[2] << "\n";
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t = 1;
  cin >> t;
  for (int i = 1; i <= t; i++) {
    check();
  }
  return 0;
}
