Answer:
a(5) = -2560
Step-by-step explanation:
The general form of the equation of a geometric series is
a(n) = a(1)*(r)^(n-1),
where a(1) is the first term, r is the common ratio.
Here, a(1) = -10 and r = 4, so
a(n) = -10(4)^(n-1).
The fifth term of this sequence is a(5) = -10(4)^(5-1), or
a(5) = -10(4)^(4), or a(5) = -10(4)^4 = -2560
