Answer:
[tex]\boxed{\bold{ab+9a-6}}[/tex]
Step-by-step explanation:
Remove parenthesis: (a) = a
[tex]\bold{2ab+9a-4-\left(ab+2\right)}[/tex]
[tex]\bold{-\left(ab+2\right): \ -ab-2}[/tex]
[tex]\bold{2ab+9a-4-ab-2}[/tex]
Simplify [tex]\bold{2ab+9a-4-ab-2}[/tex]
[tex]\bold{ab+9a-6}[/tex]
Regards,
Mordancy