To solve or simplify the expression $\sqrt{x^2 - 9x}$, there are a few possible approaches depending on what you're looking for.

Case 1: Simplification

We start with the expression: $\sqrt{x^2 - 9x}$ This is already in its simplest form. There's no further simplification unless we factor the quadratic expression inside the square root.

Factoring $x^2 - 9x$: $x^2 - 9x = x(x - 9)$ So, the expression becomes: $\sqrt{x(x - 9)}$

Case 2: Solving the Equation (if you meant $\sqrt{x^2 - 9x} = 0$)

If you want to solve for $x$ where the expression equals zero, set: $\sqrt{x^2 - 9x} = 0$ Square both sides: $x^2 - 9x = 0$ Factor the quadratic: $x(x - 9) = 0$ Thus, $x = 0$ or $x = 9$.

Would you like further details on this, or do you have any questions?

Related Questions:

1. What is the domain of $\sqrt{x^2 - 9x}$?
2. How would you solve $\sqrt{x^2 - 9x} = 5$?
3. What does the graph of $\sqrt{x^2 - 9x}$ look like?
4. Can we simplify the expression if we know more about the values of $x$?
5. How would we compute the derivative of $\sqrt{x^2 - 9x}$?

Tip:

Always ensure the expression inside a square root is non-negative to avoid complex numbers when working in real-number contexts.