Let's simplify the given equation;
-f(x)=2(3)x+1+4
f(x)=-(2(3)x+5)
f(x)=-2(3)x-5
Now, let's find g(x)
g(x)=(-2×2)(3)x-5
g(x)=-4(3)x-5
Finally, let's find (g o g)(x);
=-4(3)(g(x))-5
=-4(3)(-4(3)x-5)-5
=-12(-12x-5)-5
=144x+60-5
=144x+55
Hope I helped :)