#include<stdio.h>
#include<math.h>
main()
{
	float delta,x1,x2,a,b,c;
	printf(" gia tri a : \n");
	scanf("%f",&a);
	printf(" gia tri b : \n");
	scanf("%f",&b);
	printf(" gia tri c : \n");
	scanf("%f",&c);
	delta=b*b-4*a*c;
	if(a==0)
	{
		printf(" phuong trinh co nghiem duy nhat X=%f\n",-c/b);
	}
	else
	{
		if(delta<0)
		{
			printf(" phuong trinh vo nghiem ");
		}
		if(delta==0)
		{
			printf(" phuong trinh co nghiem kep X1=X2= %f\n",-b/(2*a));
		}
		if(delta>0)
		{
			printf(" phuong trinh co hai nghiem phan biet :\n");
			printf(" 	X1=%f\n",(-b-sqrt(delta))/(2*a));
			printf(" 	X2=%f\n",(-b+sqrt(delta))/(2*a));
		}
	}
}