Question

Розвязати систему рівнянь:3х+у=-6;5х-2у=1

Answer 1

$\displaystyle\bf\\\left \{ {{3x+y=-6} \ |\cdot 2 \atop {5x-2y=1}} \right. \\\\\\+\left \{ {{6x+2y=-12} \atop {5x-2y=1}} \right. \\----------\\11x=-11\\\\x=-11:11=-1\\\\y=-6-3x=-6-3\cdot(-1)=-6+3=-3\\\\Otvet: \ (-1 \ ; \ -3)$