Find the first term, the common difference, and give a recursive formula for the arithmetic sequence.
-8 th term is $62 ; 13$ th term is 42
A) $a _ { 1 } = 90 , d = 4 , a _ { n } = a _ { n - 1 } + 4$
B) $a _ { 1 } = 94 , d = - 4 , a _ { n } = a _ { n - 1 } - 4$
C) $a _ { 1 } = 94 , d = 4 , a _ { n } = a _ { n - 1 } + 4$
D) $a _ { 1 } = 90 , d = - 4 , a _ { n } = a _ { n - 1 } - 4$

Question

Quizplus · Accepted Answer

The common difference $d$ is $-4$ because the sequence decreases by 20 over 5 terms. The first term $a_1$ is 90, calculated using the formula for the nth term of an arithmetic sequence. The recursive formula is $a_n = a_{n-1} - 4$.

Find the First Term, the Common Difference, and Give a Recursive