If f(x) = (3+x)/ (x-3),what is f(a+ 2)?

To answer items such as this, we directly substitute the a + 2 to the all the x's in the function such that,
f(a + 2) = (3 + a + 2) / (a + 2 - 3)
Simplifying the function generated above,
f(a + 2) = (5 + a) / (a - 1)

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