An arithmetic sequence is defined
recursively by
an= an-1 - 5.5. The
first term of the
sequence is 7.5. Write
the explicit formula
for the sequence.

an = 7.5 - 5.5(n - 1).

Step-by-step explanation:

The common difference d = -5.5.

The first term is given as 7.5.

Explicit formula is

an = a1 + (n - 1)d

= 7.5 + (n - 1)-5.5

= 7.5 - 5.5(n - 1)

step-by-step explanation:

let pq = qr = rs = x, and xz = y and zu = z.

if the horizontal lines are parallel, then corresponding segments are in proportion:

substitute:

therefore 3 = y = z.

xu = y + z → xu = 3 + 3 = 6