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