a) \(2^{3x-1}=16\)
\(\Leftrightarrow2^{3x-1}=2^4\)
\(\Leftrightarrow3x-1=4\)
\(\Leftrightarrow3x=5\)
\(\Leftrightarrow x=\dfrac{5}{3}\)
b) \(\log_3\left(2x-5\right)=2\)
\(\Leftrightarrow\log_3\left(2x-5\right)=\log_33^2\)
\(\Leftrightarrow2x-5=9\)
\(\Leftrightarrow2x=14\)
\(\Leftrightarrow x=7\)