Answer:
-3mn + 14n - m is your answer.
Explanation:
Combine like terms (terms with the same amount of variables). Reorder so that it is so:
(-5mn + 2mn) + (6n + 8n) + (-4m + 3m)
Combine like terms. Add or subtract the variables. Note that if there is no number, it is assumed that there is a 1:
(-5mn + 2mn) = (2mn - 5mn) = -3mn
(6n + 8n) = 14n
(-4m + 3m) = 3m - 4m = -m
(-3mn) + (14n) + (-m)
-3mn + 14n - m is your answer.
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