Question

Решите систему уравнения 2x2-y=6 x-y=3

Answer 1

$\left \{ {{2x^{2}-y=6} \atop {x-y=3}} \right.$

$\left \{ {{2x^{2}-y=6 } \atop {y=-3+x}} \right.$

$2x^{2} -(-3+x)=6$

$2x^{2} +3-x=6\\2x^{2}+3-x-6=0\\2x^{2} -3-x=0$

x1=-1  x2=3/2

y1=-3-1=-4

y2=-3+3/2=-3/2

(x1;y1)=(-1;-4)

(x2;y2)=(3/2;-3/2)