Respuesta :

4 + n -9 = -9 + 1 + 2n + 12

Answer is n = -9
Hey there,
4 + n - 9 = - 9 + 1 + 2n + 12
n -2n = -9 + 1 + 12 + 4 - 9
-n = 9
n = - 9

Hope this helps :))

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