log a^2 = log x ⇒a^2 = x .........(Eq.1)
b^3 = log y ............... (Eq.2)
3a^2 - 2b^3 = 6 log z
Substituting a^2 & b^3 from Eq.1 & Eq.2
3x - 2 log y = 6 log z
3x = 2 log y + 6 log z
3x = log y^2 + log z^6 (Since a log b = log (b)^a )
3x = log (y^2 z^6 ) (Since log a + log b = log ab )