Question

розв'яжіть систему рівнянь​

Answer 1

$left { {{y^{2}+2xy=4} atop {x=2+y}} right. \\left { {{y^{2}+2y*(2+y)-4=0} atop {x=2+y}} right.\\left { {{y^{2}+4y+2y^{2}-4=0} atop {x=2+y}} right.\\left { {{3y^{2}+4y-4=0 } atop {x=2+y}} right.\\3y^{2}+4y-4=0\\D=4^{2}-4*3*(-4)=16+48=64=8^{2}\\y_{1}=frac{-4-8}{6}=-2\\y_{2}=frac{-4+8}{6}=frac{2}{3}\\x_{1}=2+(-2)=2-2=0\\x_{2}=2+frac{2}{3}=2frac{2}{3}\\Otvet:boxed{(0;-2),(2frac{2}{3};frac{2}{3})}$