Question

Решите систему уравнений методом подстановки
а) у = х + 1
х^2 + 2y = 1
Б) х^2 + xy = 5
y + x = 2

Answer 1

$left { {{y=x+1,} atop {x^2+2y=1;}} right. left { {{y=x+1,} atop {x^2+2(x+1)-1=0;}} right. left { {{y=x+1,} atop {x^2+2x+1=0;}} right. left { {{y=x+1,} atop {(x+1)^2=0;}} right. left { {{y=x+1,} atop {x+1=0;}} right. left { {{x=-1,} atop {y=0.}} right.$

$left { {{x^2+xy=5,} atop {y+x=2;}} right. left { {{y=2-x,} atop {x^2+x(2-x)=5;}} right. left { {{y=2-x,} atop {2x=5;}} right. left { {{x=2,5,} atop {y=-0,5.}} right.$