find (g o f)(x) where f(x)= x^2-2, g(x)=5x-8

[tex]\bf \begin{cases} f(x)=x^2-2\\ g(x)=5x-8\\ (g\circ f)(x)\implies g(~~f(x)~~) \end{cases} \\\\\\ g(~~f(x)~~)=5[f(x)]~-~8\implies 5[x^2-2]~-~8 \\\\\\ ~~~~~~~~~~~~~~~~~~ 5x^2-10-8\implies 5x^2-18[/tex]