Question

Способом сложения, даю 30 баллов

Answer 1

$\left \{ {{3x+4y=10 \: |\: *7} \atop {5x-7y=3\: |\: *4}} \right. \\\\\left \{ {{21x+28y=70} \atop {20x-28y=12}} \right. \\\\41x=82\\x=2\\\\5*2-7y=3\\y=1\\\\Otvet: (2;\:1)$