Respuesta :

[tex]x^2 + 4y^2 + 6x-40y+9 =0\\x^2 + 6x+9+4y^2-40y=0\\x^2+6x+9+4y^2-40y+100-100=0\\(x+3)^2+(2y-10)^2=100[/tex]

P.S. Hello from Russia