Respuesta :

joudi7

Answer:

-19n^4 - 8m^2 - 12m^4n

Step-by-step explanation:

8m^2 + 12m^4n + 9mn

-

19n^4 9mn

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-19n^4 - 8m^2 - 12m^4n

Answer:

The answer is B.) -31m^4n-8m^2