Question

Решите {x y=3 {5x-2y=1

Answer 1

$\left \{ {{x+y=3} \atop {5x-2y=1}} \right. \\ \left \{ {{x=3-y} \atop {5x-2y=1}} \right.$
5(3-y)-2y-1=0
15-5y-2y-1=0
-7y=-14
y=2
x=3-2=1