The answer would be a positive 15.1 or +15.1 because the positive number is greater than the negative which would make your answer positive, thats why you got it wrong :)
Sent a picture of the solution to the problem (s).
well, the recursive rule of aₙ = aₙ₊₁ + 7, where a₁ = 15, is simply saying that
we start of at 15, and the next term is obtained by simply adding 7, and so on.
well, that's the recursive rule.
so then let's use that common difference and first term for the explicit rule.

Answer:
x = 38
y = 41
z = 123
Step-by-step explanation:
x + y + z = =202
y = x + 3
z = 3y = 3(x + 3) = 3x + 9
<u>x</u> + <u>y</u> + <u>z</u> = <u>x</u> + <u>x + 3</u> + <u>3x + 9</u> = 5x + 12 = 202
5x + 12 = 202
5x = 190
x = 38
y = x + 3 = 41
z = 3y = 123
A
this is a geometric sequence since there exists a common ratio r between the terms
r =
=
=
= 3
B
to obtain the next term in the sequence multiply the previous term by 3
= 3
← recursive rule
C
the n th term of a geometric sequence is
=

where
is the first term in the sequence
= 7 ×
← explicit rule