Question

Write a recursive formula for the explicit formula.

Answer 1

Answer: A

Step-by-step explanation:

$A_n=9+(n-1)*(-4)\\\\A_1=9+(1-1)*(-1)=9+0=9\\\\A_{n-1}=9+((n-1)-1)*(-4)\\\\A_n-A_{n-1}=9+(n-1)*(-4)-(9+(n-2)*(-4))=-4n+4+4n-8=-4\\\\\boxed{A_n=A_{n-1}-4}\\\\\\Answer\ A$