Respuesta :

Answer:

3 (3a-6b+7c)

Step-by-step explanation:

Answer:

Step-by-step explanation:

The highest common factor is 3.

9/3 = 3

18/3 =6

21/3 = 7

The literals have no common factors that we know of.

Answer: 3(3a - 6b + 7c)