Respuesta :

ashleycruzan
I think the answer would just be 12a because -9a? And +9a? Would cancel out and the -10 and +10 would cancel out so all that is left is the 12a
NutellaQueen

Answer:

12a

Step-by-step explanation:

Because -9a and 9a would get rid of themselves the only "a-value" left is 12a. 10 and -10 also cancel each other out so 12a is all that is left.

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