Assuming $7x^{3}2y^2-5xy=0$ defines $y$ as a differentiable function of $x,$ use the theorem $\frac{dy}{dx}=-\frac{F_x}{F_y}$ to find $\frac{dy}{dx}$ at the point $(-1,1).$

$\frac{dy}{dx}{|}_{(-1,1)}||=$

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$($Type an integer or a simplified fraction.$)$