Question

{X=2y-7
{3x+5y=12
Решите уравнение

Answer 1

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

Answer 2

Пасиб очень помог

Answer 3

х=2у-7
{
3х+5у=12

3•(2у-7)+5у=12
6у-21+5у=12
6у+5у=12+21
11у=33
у=3

х=2•3-7=6-7= -1
Ответ: (-1;3)

Answer 4

Пасиб