Part 1 of 2 Evaluate the function $f(x)=5 x-4$ at the given value of the variable. a. $f(9)$ b. $f(0)$ a. $f(9)=$ (Simplify your answer.)

Step 1 ：The function \(f(x)\) is a linear function, and we are asked to evaluate it at \(x=9\). This means we need to substitute \(x=9\) into the function and simplify the result.

Step 2 ：Substitute \(x=9\) into the function \(f(x)=5x-4\) to get \(f(9)=5*9-4\).

Step 3 ：Simplify \(f(9)=5*9-4\) to get \(f(9)=41\).

Step 4 ：Final Answer: \(\boxed{41}\)