Answer:
[tex]f(x) = 2x + 1 \\ g(x) = {x}^{2} - 7 \\ (f + g)(x) = f(x) + g(x) \\ (f + g)(x) = (2x + 1) + ( {x}^{2} - 7) \\ (f + g)(x) = 2x + 1 + {x}^{2} - 7 \\ \boxed{ (f + g)(x) = {x}^{2} + 2x - 6}[/tex]