Answer:
9 should be the greatest common factor. (I think) because 3b² =9b
12b⁴=48b
3*(4b^4-b^2)
Step-by-step explanation:
you are looking for the greatest number who can be divided by the number(3) and the other number(12) , the greates common factor here is 3
and then take out the 3
so 3*(4b^4-b^2)
