<u>Answer</u>
6
<u>Explanation</u>
let n be the first even number in the sequence.
The 2nd term = n + 2
3rd term = n + 2 + 2
= n + 4
4th term = n + 4 + 2
= n + 6
The sum of these number = 36.
∴ n + (n +2) + (n + 4) + (n + 6) = 36
4n + 12 = 36
4n = 36 - 12
4n = 24
n = 24/4
= 6
The first term is 6.
Answer:
an = -39 -100(n -1)
Step-by-step explanation:
The given sequence can be described by a 3rd degree polynomial.* However, we suspect a typo, and that your intention is to have a formula for the arithmetic sequence ...
-39, -139, -239, -339
This has a first term a1 = -39, and a common difference d = -100.
The model for the explicit formula is ...
an = a1 +d(n -1)
Filling in the given values, the formula you seek is ...
an = -39 -100(n -1)
_____
* That polynomial is ...
an = 50n^3 +350n^2 -800n +461
This gives a sequence that starts ...
-39, -139, -139, -339, -1039, -2539, -5139, -9139, ...
So first you do length x width x height in this case 1.4 x 1.4 x 1.4
