Question

Решите систему пожалуйста

Answer 1

б)

$left { {{3x+y=4} atop {2x-2y=0}} right.\\left { {{3x+y=4} atop {x-y=0}} right. \\left { {{y=x} atop {3x+x=4}} right\\left { {{4x=4} atop {y=x}} right.\\left { {{x=1} atop {y=1}}} right.$

в)

$left { {{3x+y=4} atop {2x-2y=0}} right.\\+left { {{3x+y=4} atop {x-y=0}} right.\------\4x=4\x=1\y=x\y=1$

Ответ : (1 ; 1)

a)