Question

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

a7=−5

a subscript 7 baseline equals negative 5

a7=−1

a subscript 7 baseline equals negative 1

a7=−9

a subscript 7 baseline equals negative 9

a7=−4
a subscript 7 baseline equals negative four

Answer 1

a7 = -5

Reason: common difference = 15-19 = -4, so a_n = 19 + (n-1)(-4). Thus a7 = 19 - 4·6 = 19 - 24 = -5.