\[
\boxed{
 \left( y \left( x \right)  \right) ^{2} \left( {\frac {\rm d}{{\rm d}x}}y \left( x \right)  \right) ^{2}+2\,axy \left( x \right) {\frac {\rm d}{{\rm d}x}}y \left( x \right) + \left( 1-a \right)  \left( y \left( x \right)  \right) ^{2}+a{x}^{2}+ \left( a-1 \right) b=0}
\]