Answer:
c is the correct answer
5b + 9
Step-by-step explanation:
You are essentially trying to simplify the expression given to you. To do so, combine terms with like terms:
4b + 9 + b
In this case, combine all terms with the same amount of variables, b.
(4b + b) + 9 = 5b + 9
5b + 9 is your answer.
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