Question

What is the 9th term of the arithmetic sequence with the first term as -2 and the common difference as 5?

Answer 1

`\bf n^(th)\textit{ term of an arithmetic sequence} \\\\ a_n=a_1+(n-1)d\qquad \begin{cases} n=n^(th)\ term\\ a_1=\textit{first term's value}\\ d=\textit{common difference}\\ ----------\\ a_1=-2\\ d=5\\ n=9 \end{cases} \\\\\\ a_9=-2+(9-1)5\implies a_9=-2+40`