The expression you provided is:

$-\frac{1}{15} + \left(-\frac{1}{9}\right)$

Step-by-step solution:

1. Rewrite the expression: $-\frac{1}{15} - \frac{1}{9}$

2. Find the least common denominator (LCD): The denominators are 15 and 9. The least common denominator (LCD) of 15 and 9 is 45.

3. Rewrite each fraction with the LCD: $-\frac{1}{15} = -\frac{3}{45}, \quad -\frac{1}{9} = -\frac{5}{45}$

4. Add the fractions: $-\frac{3}{45} - \frac{5}{45} = -\frac{8}{45}$

Final Answer:

$-\frac{8}{45}$

Let me know if you would like more details on the steps. Here are five related questions to explore further:

1. How do you find the least common denominator (LCD) between two fractions?
2. What are the rules for adding and subtracting fractions?
3. How do you simplify a fraction to its lowest terms?
4. What are common mistakes when dealing with negative fractions?
5. How would you handle subtraction between two improper fractions?

Tip: Always check if the result can be simplified further, though in this case, $-\frac{8}{45}$ is already in its simplest form.