Explicit equations for the nth term of an arithmetic sequence follow a certain format.
a_n= a_1+( n-1) d
In this form, a_1 is the first term in the sequence, d is the common difference, and n is the position of the desired term in the sequence. We are given that a_1= 9 and d= 3, so we can substitute these values to write the equation.
a_n= 9+( n-1) 3
Let's also simplify this equation.
