The expression $\sqrt{8} + 3\sqrt{2}$ can be simplified by expressing $\sqrt{8}$ in terms of $\sqrt{2}$.

First, simplify $\sqrt{8}$:

$\sqrt{8} = \sqrt{4 \times 2} = \sqrt{4} \times \sqrt{2} = 2\sqrt{2}$

Now substitute this back into the original expression:

$\sqrt{8} + 3\sqrt{2} = 2\sqrt{2} + 3\sqrt{2}$

Combine the like terms:

$2\sqrt{2} + 3\sqrt{2} = (2 + 3)\sqrt{2} = 5\sqrt{2}$

So, the simplified expression is:

$5\sqrt{2}$

Would you like more details on this process or have any other questions?

Here are 5 related questions you might find interesting:

1. How do you simplify the square root of a product?
2. What is the process for adding or subtracting radical expressions?
3. How do you simplify an expression like $\sqrt{50} + 2\sqrt{2}$?
4. Can you combine radicals with different radicands (like $\sqrt{2} + \sqrt{3}$)?
5. How do you multiply and divide expressions involving square roots?

Tip: When simplifying square roots, always look for perfect squares within the radicand that can be factored out.