Homogeneous Initial Value Differential Equation

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Im trying to solve this D.E:

$$(x^2-xy+y^2)dx+(-xy)dy=0, y(1)=0$$

After I subsituted $$y=ux$$ $$dy=xdu+udx$$

I get $$-ln(x)=ln(1-u)-1+u+c$$

Answer: $$-xln(x-y)=y$$

assume () are absolute value

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After the substitution we get

\begin{align*} &&x^2(1-u+u^2)dx-ux^2(xdu+udx)&=0\\[3pt] \iff &&x^2(1-u)dx-ux^3du&=0 \\[3pt] \implies &&\frac{dx}{x}+\left(1-\frac{1}{1-u}\right)du&=0\qquad x(1-u)\neq 0\\[3pt] \implies &&\ln|x|+u-\ln|1-u|&=c\\[3pt] \implies &&x\left(1-u\right)&=\pm e^{c-u}\\[3pt] \implies &&x-y&=Ce^{-y/x}\qquad\text{where }C=\pm e^{-c}\\[3pt] \end{align*} From the initial condition we find $C=1$, and then $$\boxed{\color{blue}{x-y=e^{-y/x}}}$$ Which is an implicit solution.