Question

Решите систему уравнений:
x-2y=7
3x+2y=-3

Answer 1

$\left \{ {{x-2y=7} \atop {3x+2y=-3}} \right.$
$\left \{ {{x=7+2y} \atop {3*(7+2y)+2y=-3}} \right.$
$\left \{ {{x=7+2y} \atop {21+6y+2y=-3}} \right.$
$\left \{ {{x=7+2y} \atop {8y=-24}} \right.$
$\left \{ {{x=7+2*(-3)} \atop {y=-3}} \right.$
$\left \{ {{x=1} \atop {y=-3}} \right.$