Answer:
2b + 24x
Step-by-step explanation:
Simplify terms with the same variables:
7b + 3x - 5b + 21x = (7b - 5b) + (3x + 21x)
Simplify. Combine like terms:
(7b - 5b) = 2b
(3x + 21x) = 24x
2b + 24x is your answer.
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