Question

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

Answer 1

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