The set $L = \{3, 4, 5, 6, 7, 8, 9\}$ can be expressed in set-builder notation by describing the common property shared by all the elements in the set.

The elements are consecutive integers starting from 3 and ending at 9. Therefore, the set-builder notation for this set is:

$L = \{ x \in \mathbb{Z} \mid 3 \leq x \leq 9 \}$

Here, $\mathbb{Z}$ represents the set of all integers, and the condition $3 \leq x \leq 9$ specifies that $x$ is an integer within that range.

Would you like more details or have any questions about set-builder notation?

Here are 5 related questions you might find interesting:

1. How would you express a set of even numbers between 10 and 20 in set-builder notation?
2. Can you describe the set of all odd numbers greater than 1 in set-builder notation?
3. How would you write the set of all integers $x$ such that $x^2 < 16$ in set-builder notation?
4. What is the set-builder notation for the set of all prime numbers less than 20?
5. How would you write the set of all multiples of 5 between 15 and 50 in set-builder notation?

Tip: Set-builder notation is a concise way to describe sets, especially when the elements follow a specific rule or pattern.