\[ (a-b) y(x)^2 y'(x)^2-a b+a y(x)^2-b x^2-2 b x y(x) y'(x)=0 \] ✓ Mathematica : cpu = 0.908565 (sec), leaf count = 100
DSolve[-(a*b) - b*x^2 + a*y[x]^2 - 2*b*x*y[x]*Derivative[1][y][x] + (a - b)*y[x]^2*Derivative[1][y][x]^2 == 0,y[x],x]
\[\left \{\left \{y(x)\to -\frac {\sqrt {-a b+a x^2-2 a c_1 x+a c_1{}^2+b^2-b x^2}}{\sqrt {b-a}}\right \},\left \{y(x)\to \frac {\sqrt {-a b+a x^2-2 a c_1 x+a c_1{}^2+b^2-b x^2}}{\sqrt {b-a}}\right \}\right \}\] ✓ Maple : cpu = 1.176 (sec), leaf count = 220
dsolve((a-b)*y(x)^2*diff(y(x),x)^2-2*b*x*y(x)*diff(y(x),x)+a*y(x)^2-b*x^2-a*b = 0,y(x))
\[y \left (x \right ) = \frac {\sqrt {\left (a -b \right ) b \left (x^{2}+a -b \right )}}{a -b}\]