the roots

public class Main {

    public static void main(String[] args) {

        System.out.println("Квадратное уравнение: x^2+7x+10=0");

        int d;
        int b=7;
        int a=1;
        int c=10;
        double x1;
        double x2;

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

        x1 = (-b + Math.sqrt(d))/2;
        x2 = (-b - Math.sqrt(d))/2;

        System.out.println("Его корни: "+x1+" "+x2);
    }
}