Answer:
2a +ab-9
Explanation:
First, write out what you have:
3a-2b-ab-(a-b+ab)+3ab+b-9
Then, distribute the "-" to the "a-b+ab" inside the parenthesis:
3a-2b-ab-a+b-ab+3ab+b-9
Finally, combine like terms and simplify:
3a-a-2b+b+b-ab+3ab-ab-9
2a-2b+2b+3ab-2ab-9
2a+0+ab-9
2a+ab-9 is you equation fully simplified