Answer :
Given : f(x) = 3x + 10 and g(x) = x - 2
To Find : f(g(5))
[tex]:\implies\sf\:g(x) = x-2[/tex]
[tex]:\implies\sf\:g(5) = 5-2[/tex]
[tex]:\implies\bf\:g(5) = 3[/tex]
Now,
[tex]:\implies\sf\:f(x)=3x+10[/tex]
[tex]:\implies\sf\:f(g(5))=3x+10[/tex]
[tex]:\implies\sf\:f(3)=3(3)+10[/tex]
[tex]:\implies\sf\:f(3)=9+10[/tex]
[tex]:\implies\boxed{\bf{\blue{f(3)=19}}}[/tex]
