Question

Решите систему уравнений методом сложения: { 2 x + 7 y = − 37 2 x − y = 3

Answer 1

$left { {{2x+7y=-37|*(-1)} atop {2x-y=3}} right. Longrightarrow left { {{-2x-7y=37} atop {2x-y=3}} right. \\\\+left { {{-2x-7y=37} atop {2x-y=3}} right. \---------\-8y=40\y=-5\\2x-(-5)=3\2x+5=3\2x=-2\x=-1$

Ответ: х=-1; у=-5