Question

12. What is the 7th term of the geometric sequence where a1 = -4 and a5 = -1,024?

Answer 1

The n-th term of a geometric sequence is:
\[a _{n} = a _{1} r ^{n-1}\]
You have
\[a _{5} = a _{1} r ^{5-1}\]
-1024 = -4(r^4)
r^4 = 256
r = 4
Now that you know r, use the formula for the n-th term with a1=-4 and n = 7.

Answer 2

-21844?

Answer 3

a7 = a1(r^6)
a7 = -4(4^6)
a7 = -16384