Question

решите систему
$\left \{ {{\frac{2}{x}+x-y=-2 } \atop {3x+y=11}} \right.$

Answer 1

Ответ:

Пошаговое объяснение:

$\displaystyle\\\left \{ {{\dfrac{2}{x} +x-y=-2} \atop {3x+y=11}} \right. \\\\x\neq 0\\\\\left \{ {{2+x^2-x(11-3x)=-2x} \atop {y=11-3x}} \right. \\\\\\\left \{ {{2+x^2-11x+3x^2+2x=0} \atop {y=11-3x}} \right. \\\\\\\left \{ {{4x^2-9x+2=0} \atop {y=11-3x}} \right. \\\\\\D=b^2-4ac=81-4\cdot4\cdot2=49\\\\x_1=(9+7)/8=2;~~y_1=11-6=5\\\\x_2=(9-7)/8=0,25;~~y_2=11-3\cdot0,25=10,25\\\\Otvet:(2;5)~(0,25;10,25)$