Question

срочно даю 45 балов
$\left \{ {{x+y=12} \atop {x-y=2}} \right. \left \{ {x+y=19{} \atop {-x+y=1}} \right.$

Answer 1

х+у=12
х=2+у

2+у+у=12
у=5

х= 2+5
х= 7



х+у=19
у=1+х

х+1+х=19
х=9

у=1+9
у=10