The expression provided is:

$(-9)^2 - (-8 + 1) \times (-6)$

Let's break down the calculation step by step:

1. Evaluate the exponentiation: $(-9)^2 = 81$

2. Simplify inside the parentheses: $-8 + 1 = -7$

3. Multiply the result by $-6$: $-7 \times (-6) = 42$

4. Subtract the results: $81 - 42 = 39$

So, the final answer is:

$\boxed{39}$

Would you like more details or have any further questions?

Here are some related questions:

1. What is the difference between $(-9)^2$ and $-9^2$?
2. How does the distributive property work in expressions like this?
3. How would the expression change if the multiplication involved a positive number instead of $-6$?
4. Can you solve a similar expression with variables instead of numbers?
5. What is the order of operations used in this problem?

Tip: Always remember to follow the order of operations (PEMDAS/BODMAS) when evaluating mathematical expressions to avoid mistakes.