Program to finding the roots of quadratic equation

#include<stdio.h>
#include<conio.h>
#include<math.h>
void main()
{
  float a,b,c,d,root1,root2;
  clrscr();
  printf("Enter a b c \n");
  scanf("%f%f%f",&a,&b,&c);
  d=b*b-4*a*c;   /* finding determinant */   
   if(d==0)      /* when d is 0 both the roots will be equal */
          {
            printf("\n roots are equal \n");
            root1=root2=-b/(2*a);
            printf("root1=%.3f \n root2=%.3f", root1,root2);
          }
    else
     if(d>0)     /* roots are real and distinct */
           {
             printf("\n roots are real and distinct \n");
             root1=(-b+sqrt(d))/(2*a);
             root2=(-b-sqrt(d))/(2*a);
             printf("root1=%.3f\n root2=%.3f",root1,root2);
            }
     /* when d is -ve it is not possible to take the squareroot of -ve number,
              we have to take absolute value of d */
     else
          {
            printf("\n roots are imaginary \n");
            root1=-b/(2*a);
            root2=sqrt(-d)/(2*a);
            printf("real part=%.3f \n imaginary part = %.3f", root1,root2);
           }
getch();
}
     Output 1:
     Enter a b c
     2 2 2
     roots are imaginary 
     real part=-0.500
     imaginary part=0.866

     Output 2:
     Enter a b c
     2 5 1
     roots are real and distinct
     root1=-0.219
     root2=-2.281

     Output 3:
     Enter a b c 
     1 2 1
     roots are equal
     root1=-1.000
     root2=-1.000