Answer:
a8 = -128x^8 -384x^7
Explanation:
The formula for the general term of a geometric sequence with first term a1 and common ratio r is ...
an = a1·r^(n-1)
Here, we have a1 = (x+3) and r = (-2x^2-6x)/(x+3) = -2x. Then the 8th term is ...
a8 = (x+3)(-2x)^(8-1)
a8 = -128x^8 -384x^7