Find the Roots of a Quadratic Equation

#include <stdio.h>
#include <math.h>
int main()
{
    double a, b, c;
    double D;
    double r1, r2;

    printf("Enter the value of a: ");
    scanf("%lf", &a);
    printf("Enter the value of b: ");
    scanf("%lf", &b);
    printf("Enter the value of c: ");
    scanf("%lf", &c);

    D = b*b - 4*a*c;

    if(D < 0)
        printf("Roots are imaginary\n");
    else
    {
        r1 = (-b + sqrt(D)) / (2*a);
        r2 = (-b - sqrt(D)) / (2*a);

        printf("Root 1 = %lf\n", r1);
        printf("Root 2 = %lf\n", r2);
    }

    return 0;
}