Question

Given the first five terms of the sequence 19, 15, 11, 7, 3 . . .
, use subscript notation to describe a7
.(1 point)
Responses

a7=−9

a subscript 7 baseline equals negative 9

a7=−1

a subscript 7 baseline equals negative 1

a7=−5

a subscript 7 baseline equals negative 5

a7=−4

a subscript 7 baseline equals negative 4

Answer 1

Find the common difference: 15−19 = −4, so a_n = 19 + (n−1)(−4) = 23 − 4n.
Thus a_7 = 23 − 4(7) = 23 − 28 = −5.

Answer: a_7 = −5.