What is the GCF of 9 and 0?

Rules for GCF Involving Zero

• The divisors of the given number (e.g. n1) are all numbers that can divide n1 without leaving a remainder.
• Zero is divisible by any integer.
• Therefore, the set of common divisors of 0 and n1 is exactly the set of divisors of n1.

1. Divisors of Zero:
   • Every integer divides zero. This is because zero divided by any integer is zero (i.e., 0 ÷ 9 = 0 for any integer).
2. Divisors of a Non-Zero Number:
   • Divisors of 9: 1, 3, 9
3. Common Divisors:
   • The common divisors of 0 and 9 are the divisors of 9 since every integer divides 0.

Greatest Common Divisor:

The largest number in the list of common divisors is 9 itself. Hence, the GCF of 0 and 9 is 9.