Determine 8th term in the geometric sequence whose first term is -10 and whose common ratio is 2

Answer 1

Mark M's answer is correct. I'll just add that he is using the following formula, which is used for geometric sequences:

a_n = a₁*r^n-1 where a_n is the nth term and r is the common ratio.

Answer 2

a₈ = a₁(2)⁷

^a₈ = -10(128)

Answer 3

a8 = a1*r^7 = -10*2^7 = -1280