Step 1 :The first question asks to solve the equation \(f(x)=0\). This is a quadratic equation and can be solved using the quadratic formula \(x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\), where \(a\), \(b\), and \(c\) are the coefficients of the quadratic equation \(ax^2 + bx + c = 0\). In this case, \(a=1\), \(b=-3\), and \(c=-18\).
Step 2 :The solutions to the equation \(f(x)=0\) are \(x=-3\) and \(x=6\). These are the x-values where the function \(f(x)\) intersects the x-axis.
Step 3 :Final Answer: The solution set is \(\boxed{-3, 6}\).