Help me people please

xy=8 x²+y²=20 y=8/x x²+(8/x)²=20 y=8/x x²+64/x²=20 y=8/x x⁴+64=20x² x⁴-20x²+64=0 D=20²-4*64=400-256=144=12² x²₁=(20-12)/2=4     x₁₂=+-2  y₁₂=+-4 x₂²=(20+12)/2=16  x₃₄=+-4  y₃₄=+-2