C :

#include<stdio.h>
#include<math.h>
int main()
{
	double a,b,c,delt,r1,r2;
	scanf("%lf%lf%lf",&a,&b,&c);
	if(b*b-4*a*c>0)
	{
		delt=b*b-4*a*c;
		r1=(-b+sqrt(delt))/(2*a);
		r2=(-b-sqrt(delt))/(2*a);
		printf("r1=%7.2lf\nr2=%7.2lf\n",r1,r2);
	}
	return 0;
}

C++ :

#include <cstdio>
#include <cmath>
int main (void)
{
	double a,b,c,r1,r2;
	scanf("%lf%lf%lf",&a,&b,&c);
	r1=(-b+sqrt(b*b-4*a*c))/(2*a);
	r2=(-b-sqrt(b*b-4*a*c))/(2*a);
	printf("r1=%7.2f\n",r1);
	printf("r2=%7.2f",r2);
	return 0;
}

Java :

import java.util.Scanner;

import static java.lang.Math.sqrt;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        double r1, r2;
        double a, b, c;
        a = sc.nextDouble();
        b = sc.nextDouble();
        c = sc.nextDouble();
        r1 = ((-b + sqrt(b * b - (4 * a * c))) / 2 * a);
        r2 = ((-b - sqrt(b * b - (4 * a * c))) / 2 * a);
        if ((b * b - (4 * a * c)) >= 0) {
            System.out.printf("r1=%7.2f\nr2=%7.2f", r1, r2);
        } else {
            System.out.printf("No real roots!");
        }
        System.out.print("\n");
    }
}