Please please help!!! I really need help on this quarion and I keep getting it wrong :(

Answer:
[tex]f(x)=x^2+4\\g(x)=4x[/tex]
[tex](f+g)(x)=x^2+4+4x\\(f+g)(x)=x^2+4x+4[/tex]
------------------------------------------------------------------
[tex](f-g)(x)=x^2+4-(4x)\\(f-g)(x)=x^2+4-4x\\(f-g)(x)=x^2-4x+4\\[/tex]
-----------------------------------------------------------------
[tex](f*g)(x)=(x^2+4)(4x)\\(f*g)(x)=4x^3+16x[/tex]
-----------------------------------------------------------------
[tex](\frac{f}{g})(x)= \frac{x^2+4}{4x} \\[/tex]