Question

решите систему урaвнений
-x+y=-6
-4y-x^2-3

Answer 1

$left { {{-x+y=-6} atop {-4y- x^{2} =3}} right.$
$left { {{y=-6+x} atop {-4(-6=x)- x^{2} =3}} right.$
$-4(-6+x)- x^{2} =3$
$24-4x- x^{2} -3=0$
$x^{2} +4x-21=0$
$D= 4^{2} -4*(-21)=16+84=100$
$x1= frac{-4+ sqrt{100} }{2} = frac{-4+10}{2} =3$
$x2= frac{-4-10}{2} = frac{-14}{2} =-7$

$left { {{x=3} atop {y=-3}} right.$
$left { {{x=-7} atop {y=-13}} right.$
Ответ:(3;-3) и (-7;-13)