Find the first term, the common difference, and give a recursive formula for the arithmetic sequence.
-7th term is 45; 16th term is 117
A) a1 = -3, d = 8, an = an-1 - 8
B) a1 = -3, d = 8, an = an-1 + 8
C) a1 = -11, d = 8, an = an-1 - 8
D) a1 = -11, d = 8, an = an-1 + 8

Question

Quizplus · Accepted Answer

The common difference is (117 - 45) / (16 - 7) = 8. The first term is 45 - 8(7 - 1) = -3. The recursive formula is an = an-1 + 8.

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