Question

What value, written as a decimal, should Lena use as the common ratio? Lena is asked to write an explicit formula for the graphed geometric sequence. On a coordinate plane, 3 points are plotted. The points are (1, 1), (2, 2.5), (3, 6.25).

Answer 1

a(n) = 1(2.5)^(n - 1)

Explanation:

The geometric sequence is 1, 2.5, 6.25, 15.625, and so on; the first term is 1. The common ratio is 2.5; each new term is 2.5 times the previous term.

The explicit formula desired is thus a(n) = 1(2.5)^(n - 1)

Answer 2

ITS CCCCCCC (2.5)