Let's solve the expression:

$12 \times (9 - 10)$

First, perform the operation inside the parentheses:

$9 - 10 = -1$

Now, multiply:

$12 \times (-1) = -12$

So, the result is:

$\boxed{-12}$

Would you like further details or have any questions?

Here are 5 related questions:

1. What is $15 \times (8 - 5)$?
2. How would you solve $7 \times (4 + 3)$?
3. What happens if you change the expression to $12 \times (10 - 9)$?
4. Can you simplify $5 \times (6 - 8)$?
5. How would the result change if you had $12 \times (9 - 11)$?

Tip: Always solve the expression inside parentheses first before performing multiplication.