Answer:
13^1
Step-by-step explanation:
x = 1
[tex] \frac{ {13}^{5} }{ {13}^{x} } = {13}^{4} \\ {13}^{5 - x} = {13}^{4} \\ 5 - x = 4 \\ - x = 4 - 5 \\ - x = - 1 \\ x = 1[/tex]