Question

Use the arithmetic sequence 12, 15, 18, 21... which is equation for the nth term of the sequence

Answer 1

Answer:

            aₙ = 3n + 9

Step-by-step explanation:

$a_1=12\\a_2=15\\\\d=a_2-a_1=15-12=3\\\\a_n=a_1+d(n-1)\\\\a_n=12+3(n-1)\\a_n=12+3n-3\\a_n=3n+9$