Hey!
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Steps To Solve:
~Subtract n to both sides
3 - n = n + 4 - n
~Simplify
3 - n = 4
~Subtract 3 to both sides
3 - n - 3 = 3 - 4
~Simplify
n = -1
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Answer:
[tex]\large\boxed{n~=~-1}[/tex]
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Hope This Helped! Good Luck!