(m+n+2m-2n)(m+n-2m+2n)/(3n-m)=(3m-n)(3n-m)/(3n-m)=3m-n
x(3x+2)=0 x=0 x=-2/3
(3x+x-1)(3x-x+1)=0 x=1/4 x=-1/2