\(\displaystyle \displaystyle{6^{2\log_6x+\log_6x}=125}\)

\(\displaystyle 2\log_6x+\log_6x=\log_6(125)\)

\(\displaystyle 3\log_6x=\log_6(125)\)

\(\displaystyle \log_6(x^3)=\log_6(125)\)

\(\displaystyle x^3=125\)

\(\displaystyle x=5\)

So, to answer your question, yes.