Hey I've got a question here where I need to find an integrating factor to make an equation exact, but it's in two variables and I'm having trouble finding both values!

To do this i'm using the exactness formula $\displaystyle \frac{\partial M}{\partial y}=\frac{\partial N}{\partial x}$ Which gives me:For what values of m and n will $\displaystyle u=x^ny^m$ be an integrating factor for the differential equation

$\displaystyle (-12y+14x)dx + (4x-6x^2y^{-1})dy=0$

$\displaystyle -12(m+1)x^ny^m+14mx^{n+1}y^{m-1}=4(n+1)x^ny^m - 6(n+2)x^{n+1}y^{m-1}$

$\displaystyle -12(m+1)+14m=4(n+1)-6(n+2)$

$\displaystyle m=2-n$

But i'm not sure where to go from here to get another equation to find m and n. A push in the right direction would be awesome. Thanks for your help!

-Kasper