BT C giai Pt bac 2

// bai tap giai phuong trinh bac hai
#include<math.h>
#include<conio.h>
#include<stdio.h>
void main()
{
// Khai bao bien
float a,b,c,delta;
//In ra man hinh
printf("Cho biet he so a = ");
scanf("%f", &a);
printf("Cho biet he so b = "); scanf("%f", &b);
printf("Cho biet he so c = "); scanf("%f", &c);
// tinh delta
delta = b*b - 4*a*c;
if (delta < 0)
            printf("Phuong trinh vo nghiem");
else if (delta == 0)
            printf("Phuong trinh co nghiem kep x1 = x2 = %0.2f", -b/(2*a));
   else{
            printf ("Phuong trinh co 2 nghiem phan biet:\n x1 = %0.2f", (-b + sqrt(delta))/(2*a));
                        printf ("\nx1 = %0.2f", (-b - sqrt(delta))/(2*a));
   }
   getch();
//create by Sangvo