Answer:
4 (9x² + 6xy + y²)
Explanation:
Looking at the variables, the there is no common factor that applies for all three variables. But 36, 24, and 4 as a common factor, and the greatest is 4. 4 fits into 36, 24, and 4, so we can factor that out. Simply divide each terms by 4, then you will get:
4 (9x² + 6xy + y²)