Write a simplified expression for the right half of the equation that can be used to find the nth term in the sequence

Answer is;
[tex]a_n=3n[/tex][tex]\begin{gathered} \text{common difference (d) =6-3=3} \\ By\text{ formula, } \\ a_n=a+(n-1)d\text{ , where a=3} \\ a_n=3+(n-1)3 \\ a_n=3+3n-3 \\ a_n=3n \end{gathered}[/tex]