To find \((f \circ g)(x)\), we need to substitute \(g(x)\) into \(f(x)\).
Given:
- \(f(x) = 5x - 4\)
- \(g(x) = x^2 - 3x - 11\)
So we need to compute:
\[ f(g(x)) = f(x^2 - 3x - 11) \]
Now we will substitute \(x^2 - 3x - 11\) into \(f(x)\):
\[ f(x^2 - 3x - 11) = 5(x^2 - 3x - 11) - 4 \]
Now we distribute the 5:
\[ = 5x^2 - 15x - 55 - 4 \]
Combine the constant terms:
\[ = 5x^2 - 15x - 59 \]
Now, writing this in standard form, we get:
\[ (f \circ g)(x) = 5x^2 - 15x - 59 \]
Thus, the final answer is:
\[ \boxed{5x^2 - 15x - 59} \]