Now I have a question where I need to simplify.

9a - b - 2a - 10b

How exactly would I simplify this? My textbook is not very clear...

Combine like terms as I showed you in another post.

Yes Ma'am, thanks!

To simplify the expression 9a - b - 2a - 10b, you need to combine like terms.

Step 1: Combine the terms with the same variable (in this case, "a").
- Combine the terms 9a and -2a: 9a - 2a = 7a.

Step 2: Combine the terms with the same variable (in this case, "b").
- Combine the terms -b and -10b: -b - 10b = -11b.

Step 3: Put the simplified terms together.
- The simplified expression is 7a - 11b.

Therefore, the simplified form of the expression 9a - b - 2a - 10b is 7a - 11b.