Addition is commutative. 2+3+4 would be equal to 2+4+3, 3+2+4, and so on. In this case, since all the terms are addition, you can take out the parenthesis. That leaves you with 6b+2b+4c. Now, you can only add like terms together. You can add 6b and 2b but not 4c. C cannot combine with B. Carrots cannot combine with broccoli. So, to simplify that expression, it would be 8b+4c.
