Determine the interval of convergence for ∑n=1∞(x−4)nn⋅5n\sum_{n=1}^{\infty} \frac{(x-4)^n}{n \cdot 5^n}∑n=1∞n⋅5n(x−4)n.
[−1,9)[-1, 9)[−1,9)
(−1,9](-1, 9](−1,9]
[−1,9][-1, 9][−1,9]
(−1,9)(-1, 9)(−1,9)