Answer:
The resulting expression is;
[tex]-5-4n[/tex]Explanation:
Given the expression;
[tex]4-8n+7n-3n-9[/tex]collecting the like terms (bringing all the like terms together);
[tex]\begin{gathered} 4-8n+7n-3n-9 \\ 4-9-8n+7n-3n \\ (4-9)-8n+7n-3n \\ -5-4n \end{gathered}[/tex]Therefore, the resulting expression is;
[tex]-5-4n[/tex]