Step 1 :First, we need to solve for $x$ when $f(x) = 0$. This means we need to set the equation $5x - 1 = 0$ and solve for $x$.
Step 2 :By adding 1 to both sides of the equation, we get $5x = 1$.
Step 3 :Then, we divide both sides of the equation by 5 to solve for $x$, which gives us $x = \frac{1}{5}$.
Step 4 :Next, we need to find the values of $x$ for which $f(x) > 0$. This means we need to find the values of $x$ for which $5x - 1$ is greater than 0.
Step 5 :By adding 1 to both sides of the inequality, we get $5x > 1$.
Step 6 :Then, we divide both sides of the inequality by 5 to solve for $x$, which gives us $x > \frac{1}{5}$.
Step 7 :Final Answer: (a) The value of $x$ for which $f(x)=0$ is \(\boxed{\frac{1}{5}}\). (b) The values of $x$ for which $f(x)>0$ are \(\boxed{( \frac{1}{5}, \infty )}\).