Question

Решите систему уравнений x^2-6xy+9y^2=x-y
x-3y=-1

Answer 1

$left { {{x^2-6xy+9y^2=x-y} atop {x-3y=-1}} right. \ left { {{x^2-2*x*3y+(3y)^2=x-y} atop {x-3y=-1}} right. \ left { {{(x-3y)^2=x-y} atop {x-3y=-1}} right. \ -left { {{x-y=1} atop {x-3y=-1}} right. \ left { {{-y+3y=1+1} atop {x-y=1}} right. \ left { {{2y=2} atop {x=y+1}} right. \ left { {{y=1} atop {x=2}} right. \ left { {{x=2} atop {y=1}} right.$
Ответ: $(2;1)$