Answer:
7
Step-by-step explanation:
[tex]\dfrac{5^{11}}{5^x}=5^4\qquad\text{multiply both sides by}\ 5^x\\\\5^{11}=5^4\cdot5^x\qquad\text{use}\ a^n\cdot a^m=a^{n+m}\\\\5^{11}=5^{4+x}\iff11=4+x\qquad\text{subtract 4 from both sides}\\\\11-4=4-4+x\\\\7=x\to x=7[/tex]
