Answer:
[tex]\large\boxed{(f+g)(x)=x^2+2x-6}[/tex]
Step-by-step explanation:
[tex](f+g)(x)+f(x)+g(x)\\\\f(x)=2x+1,\ g(x)=x^2-7\\\\(f+g)(x)=(2x+1)+(x^2-7)=2x+1+x^2-7=x^2+2x-6[/tex]