Решите систему уравнения

$\left \{ {{5x^2-y^2=-4} \atop {xy=3}} \right. \\ \left \{ {{y= \tfrac{3}{x} } \atop {5x^2-( \tfrac{3}{x})^2=-4 }} \right. \\ \\ 5x^2-( \tfrac{3}{x})^2=-4 \\ 5x^2- \frac{9}{x^2}=-4 \\ 5x^4+4x^2-9=0 \\ x^2=t \\ 5t^2+4t-9=0 \\ D=16+180=196=14^2 \\ t_1= \frac{-4-14}{10}=- \frac{9}{5} \\ t_2=\frac{-4+14}{10} =1 \\1) x^2=1 \\ x_{1}=1 \\ x_{2}=-1 \\2)x^2=- \frac{9}{5}$ нет решений $y_1=3 \\ y_2=-3$