Answer :
Okay, here we have this:
Considering the provided information we obtain the following when we replace the point in the function:
[tex]\begin{gathered} y=\log _ax \\ 4=\log _a14 \end{gathered}[/tex]Now, let's solve for a:
[tex]\begin{gathered} 4=\frac{1}{\log_{14}\left(a\right)} \\ 4\log _{14}\mleft(a\mright)=1 \\ \log _{14}\mleft(a\mright)=\frac{1}{4} \\ a=\sqrt[4]{14} \end{gathered}[/tex]Finally we obtain that a is equal to ⁴√14. We can check it in the following graph resulting from the function:
