g(x) = f(x) + n - shift a graph of f(x) n units up
g(x) = f(x) - n - shift a graph of f(x) n units down
g(x) = f(x - n) - shift a graph of f(x) n units right
g(x) = f(x + n) - shift a graph of f(x) n units left
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f(x) = x
g(x) = x + 4 = f(x) + 4
Answer: Shift a graph of f(x) n units up.