We need to find g(x)/f(x) so we will put them over each other as a fraction
[tex]\frac{g(x)}{f(x)}=\frac{x^2-5}{4x+1}\text{ , x}\ne\frac{-1}{4}[/tex]In any algebraic fraction, denominators can not be zero, so we avoid any values make it equal to zero like -1/4 in our question