Question

Find the 7th term of the geometric sequence with the given terms.
a4 = -8 and a5 = -40; a7 = _______.

Answer 1

common ratio = -40/-8 = 5

now use \[a_n = a_1 r^{n-1}\]
\[a_7 = a_4 r^{4-1}\]
\[a_7 = -8 \times 5^{3}\]
solve for that