persamaan dua variabel

package javaapplication2;
import java.io.*;
class baca
{
    public static String bacaString ()
    {
        int karakter;
        String str="";
        boolean selesai = false;
        while (!selesai)
        {
            try
            {
                karakter = System.in.read ();
                if (karakter<0 || (char) karakter =='\n')
                {
                    selesai = true;
                }
                else if ( (char) karakter !='r')
                {
                    str = str + (char) karakter;
                }
            }
            catch (java.io.IOException e)
            {
                System.err.println("ada kesalahan");
                selesai = true;
            }
        }
        return str;
    }
}
public class Main
{
    public static void main(String[] args)
    {
        System.out.println("masukkan koefisien x awal ");
        String a =baca.bacaString();
        int aa=Integer.parseInt(a);
        System.out.println("MAsukkan koefisien y awal ");
        String b =baca.bacaString();
        int bb =Integer.parseInt(b);
        System.out.println("MAsukkan konstanta ");
        String e =baca.bacaString();
        int ee =Integer.parseInt(e);
        System.out.println("masukkan koefisien x kedua ");
        String c =baca.bacaString();
        int cc=Integer.parseInt(c);
        System.out.println("MAsukkan koefisien y kedua ");
        String d =baca.bacaString();
        int dd =Integer.parseInt(d);
        System.out.println("MAsukkan konstanta ");
        String f =baca.bacaString();
        int ff =Integer.parseInt(f);

        double DD = ((dd*ee)+ (-bb*ff));
        double EE = ((-cc*ee)+(aa*ff));
        double FF = ((aa*dd)-(bb*cc));
        double X = (DD/FF);
        double Y = (EE/FF);
        System.out.println("hasil x =" +X );
        System.out.println("hasil y =" + Y);

    }
}