Question

{X=2y-7
{3x+5y=12
Решите уравнение

Answer 1

$\left \{ {{x=2y-7} \atop {3x+5y=12}} \right.$
$\left \{ {{x=2y-7} \atop {3*(2y-7)+5y=12}} \right.$
$\left \{ {{x=2y-7} \atop {6y-21+5y=12}} \right.$
$\left \{ {{x=2y-7} \atop {6y+5y=12+21}} \right.$
$\left \{ {{x=2y-7} \atop {11y=33}} \right.$
$\left \{ {{x=2*3-7} \atop {y=3}} \right.$
$\left \{ {{x=-1} \atop {y=3}} \right.$