The equation shown is:

$s^2 - 9 = 0$

To solve for $s$, let's follow these steps:

Step 1: Rearrange the Equation

Add 9 to both sides:

$s^2 = 9$

Step 2: Take the Square Root of Both Sides

To isolate $s$, take the square root of both sides:

$s = \pm \sqrt{9}$

Step 3: Simplify the Square Root

The square root of 9 is 3, so:

$s = \pm 3$

Final Answer

The solutions are:

$s = 3, -3$

Would you like more details on any part of the solution, or have any questions?

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Here are some related questions for further practice:

1. What are the solutions to $s^2 - 16 = 0$?
2. Solve the equation $x^2 - 25 = 0$.
3. If $s^2 - 4 = 0$, what values of $s$ satisfy this equation?
4. How would you solve $s^2 + 9 = 0$?
5. What are the steps to solve $s^2 - 1 = 0$?

Tip: For equations like $s^2 - a = 0$, remember you can always isolate $s^2$ by moving $a$ to the other side, then take the square root, considering both the positive and negative roots.