Question

Решите систему уравнений
y^2 = x + 4y
{
x + y = 4

Answer 1

$left { {{y^2=x+4y} atop {x+y=4}} right. left { {{y^2=x+4y} atop {x=4-y}} right. left { {{y^2=4-y+4y} atop {x=4-y}} right. left { {{y^2-3y-4=0}(1) atop {x=4-y}(2)} right.\(1)y^2-3y-4=0\a-b+c=0\y_1=-1\y_2=4\ (2)x_1=4+1=5\x_2=4-4=0\................................................................................\(x_1;y_1)=(0;4)\(x_2;y_2)=(5;-1)$