we are given the following polynomials:
[tex]\begin{gathered} -6n+3 \\ 4n-9 \end{gathered}[/tex]
Adding the two expressions we get:
[tex](-6n+3)+(4n-9)[/tex]
Associating like terms, that is, terms that have the same variable elevated to the same number we get:
[tex](-6n+4n)+(3-9)[/tex]
Adding like terms:
[tex]-2n-6[/tex]
An thus we get the sum of the expressions.
