#include <bits/stdc++.h>
char *fs, *ft, buf[1 << 20];
inline long long read() {
  long long x = 0, f = 1;
  char ch =
      (fs == ft && (ft = (fs = buf) + fread(buf, 1, 1 << 20, stdin), fs == ft))
          ? 0
          : *fs++;
  ;
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = (fs == ft &&
          (ft = (fs = buf) + fread(buf, 1, 1 << 20, stdin), fs == ft))
             ? 0
             : *fs++;
    ;
  }
  while (ch >= '0' && ch <= '9') {
    x = x * 10 + ch - '0';
    ch = (fs == ft &&
          (ft = (fs = buf) + fread(buf, 1, 1 << 20, stdin), fs == ft))
             ? 0
             : *fs++;
    ;
  }
  return x * f;
}
using namespace std;
const long long N = 2e5 + 1000;
const long long inf = 0x3f3f3f3f;
const long long mod = 998244353;
const double eps = 1e-6;
const double PI = acos(-1);
long long a[N];
struct node {
  long long i, j, x;
} ans[N];
signed main() {
  long long t;
  cin >> t;
  while (t--) {
    long long n;
    cin >> n;
    long long sum = 0;
    for (long long i = 1; i <= n; i++) {
      cin >> a[i];
      sum += a[i];
    }
    if (sum % n != 0) {
      cout << -1 << '\n';
      continue;
    }
    long long cnt = 0;
    for (long long i = 2; i <= n; i++) {
      ans[++cnt].i = 1;
      ans[cnt].j = i;
      ans[cnt].x = (a[i] % i == 0 ? 0 : i - a[i] % i);
      a[i] += ans[cnt].x;
      ans[++cnt].i = i;
      ans[cnt].j = 1;
      ans[cnt].x = a[i] / i;
    }
    for (long long i = 2; i <= n; i++) {
      ans[++cnt].i = 1;
      ans[cnt].j = i;
      ans[cnt].x = sum / n;
    }
    cout << cnt << '\n';
    for (long long i = 1; i <= cnt; i++)
      cout << ans[i].i << ' ' << ans[i].j << ' ' << ans[i].x << '\n';
  }
}
