Given:
[tex](8n-4)(n^2+9)[/tex]
To simplify and identify the degree:
On simplification we get,
[tex]\begin{gathered} (8n-4)(n^2+9)=8n^3+72n-4n^2-36 \\ =8n^3-4n^2+72n-36 \end{gathered}[/tex]
Therefore, the simplest form is,
[tex]8n^3-4n^2+72n-36[/tex]
And the degree of the given polynomial is 3.
