Respuesta :

Answer:

Step-by-step explanation:

[tex](f+g)(x) =f(x) + g(x)\\f(x) = x+ 5\\g(x) = 2x + 1\\(f+g)(x) = x+ 5 + 2x + 1\\(f+g)(x) = 3x + 6\\\\(f+g)(3) = 3(3) + 6 = 15[/tex]