Use implicit differentiation where LaTeX:  \displaystyle y is a function of LaTeX:  \displaystyle x to find the derivative of LaTeX:  \displaystyle - 8 \sqrt{x} e^{y} - 12 \sqrt{y} \log{\left(x \right)}=13

Taking the derivative of both sides using implicit differentiation gives: LaTeX:   - 8 \sqrt{x} y' e^{y} - \frac{6 y' \log{\left(x \right)}}{\sqrt{y}} - \frac{12 \sqrt{y}}{x} - \frac{4 e^{y}}{\sqrt{x}} = 0  Solving for LaTeX:  \displaystyle y' gives LaTeX:  \displaystyle y' = - \frac{6 \sqrt{x} y + 2 x \sqrt{y} e^{y}}{3 x^{\frac{3}{2}} \log{\left(x \right)} + 4 x^{2} \sqrt{y} e^{y}}