Answer
The recursive formula for the arithmetic sequence is: $A(n)=A(n-1) + (-7)$ where $A(1)=18$
The explicit formula is: $A(n)=18 + (n-1)(-7)$
Work Step by Step
$A(1) =18$
$A(2) = A(1) + (-7)=11$
$A(3)=A(2) + (-7)=4$
$A(4)=A(3) + (-7)=-3$
The recursive formula for the arithmetic sequence is: $A(n)=A(n-1) + (-7)$ where $A(1)=18$
$A(n)=A(n-1) +(-7)$
$A(n)=A(1) + (n-1)d$
$A(n)=18 + (n-1)(-7)$
The explicit formula is: $A(n)=18 + (n-1)(-7)$
