Respuesta :

First, write down all the factors for 9 and 12:
9) 1, 3, 9
12) 1, 2, 3, 4, 6, 12

The greatest number that both lists share is 3, so 3 is your GCF.
12: 1,2,3,4,6,12

9: 1,3,9

your answer would be 3.

That sounds about right to me. in order to find the Greatest Common Factor (GCF) look for the common factors that it has (: