#include <bits/stdc++.h>
using namespace std;
namespace IO {
char buf[1 << 23], *p1 = buf, *p2 = buf, obuf[1 << 23], *O = obuf;
inline int read() {
  int x = 0, sign = 0;
  char s =
      (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
           ? EOF
           : *p1++);
  while (!isdigit(s))
    sign |= s == '-',
        s = (p1 == p2 &&
                     (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
                 ? EOF
                 : *p1++);
  while (isdigit(s))
    x = (x << 1) + (x << 3) + (s - '0'),
    s = (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
             ? EOF
             : *p1++);
  return sign ? -x : x;
}
inline void print(int x) {
  if (x > 9) print(x / 10);
  (*O++ = x % 10 + '0');
}
}  // namespace IO
namespace math {
const int mod = 998244353;
const int maxn = 1e6 + 5;
long long ksm(long long a, long long b) {
  long long s = 1, m = a;
  while (b) {
    if (b & 1) s = s * m % mod;
    m = m * m % mod, b >>= 1;
  }
  return s;
}
long long inv(long long x) { return ksm(x, mod - 2); }
long long fc[maxn], ifc[maxn];
void init(int n) {
  fc[0] = 1;
  for (int i = 1; i <= n; i++) fc[i] = fc[i - 1] * i % mod;
  ifc[n] = inv(fc[n]);
  for (int i = n - 1; i >= 0; i--) ifc[i] = ifc[i + 1] * (i + 1) % mod;
}
long long C(long long n, long long m) {
  return fc[n] * ifc[m] % mod * ifc[n - m] % mod;
}
}  // namespace math
using namespace IO;
const int N = 3e5 + 5;
int n, a[N];
void c(int i, int j, int x) {
  cout << i << " " << j << " " << x << endl;
  a[i] -= i * x, a[j] += i * x;
  assert(a[i] >= 0);
}
void solve() {
  cin >> n;
  int sum = 0;
  for (int i = 1; i <= n; i++) cin >> a[i], sum += a[i];
  if (sum % n) {
    puts("-1");
    return;
  }
  int res = sum / n;
  cout << (n - 1) * 3 << endl;
  for (int i = 2; i <= n; i++) {
    c(1, i, a[i] % i == 0 ? 0 : i - a[i] % i);
    c(i, 1, a[i] / i);
  }
  for (int i = 2; i <= n; i++) c(1, i, res);
}
int main() {
  int t = 1;
  cin >> t;
  while (t--) solve();
  return 0;
}
