Answer:
-37x+26
Explanation:
The x-coefficients have the sequence ...
-2, -7, -12, ...
which has first term -2 and common difference of (-7 -(-2)) = -5. Then the 8th x-coefficient is ...
-2 + (-5)(8 -1) = -37
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The constants have the sequence ...
5, 8, 11, ...
which has first term 5 and common difference 8 -5 = 3. Then the 8th constant term is ...
5 +(3)(8 -1) = 26
The 8th term of the sequence is -37x +26.
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The general term of an arithmetic sequence with first term a1 and common difference d is ...
an = a1 +d(n -1)
In the above, we have used n=8 to find the 8th term.