If it is exact find a function F$($x$,$y$)$ whose differential, $(,)$dF$($x$,$y$)$ is the left hand side of the differential equation. That is$,$ level curves $(,)=$F$($x$,$y$)=$C are solutions to the differential equation:

$(12+3)+(12+3)=0(1$xy$2+3$y$)$dx$+(1$x$2$y$+3$x$)$dy$=0$