The expression given in the image is:

$-3(-9a - 9) - 4(8a - 10)$

Let's simplify this step by step.

Step 1: Distribute the -3 through the first parentheses

$-3(-9a - 9) = (-3 \times -9a) + (-3 \times -9) = 27a + 27$

Step 2: Distribute the -4 through the second parentheses

$-4(8a - 10) = (-4 \times 8a) + (-4 \times -10) = -32a + 40$

Step 3: Combine all the terms

Now, combine all terms: $27a + 27 - 32a + 40$

Step 4: Combine like terms

Combine the terms with $a$: $27a - 32a = -5a$

Combine the constants: $27 + 40 = 67$

Final Simplified Expression:

$-5a + 67$

Would you like more details or have any questions?

Here are five related questions for practice:

1. Can you simplify $5(2a + 4) - 3(3a - 5)$?
2. How would you solve $-2(6a - 4) + 5(3a + 7)$?
3. What happens when you distribute a positive number versus a negative number?
4. What is the general method for combining like terms?
5. How does factoring differ from distributing in an equation?

Tip: Always watch the signs carefully when distributing negative numbers across parentheses.