newton's square problem

package newton_sqrt;

//importing Scanner AND Math
import java.util.Scanner;
import java.lang.Math;

//class
public class Newton_square_root {

    //here's main!
    public static void main(String [] args) {

                //declaring new scanner
                Scanner keyboard=new Scanner(System.in);

                //
                System.out.print("Enter in N for Newton: ");
                int N=keyboard.nextInt();

                //this is defining the variables
                double n=(double)N;
                double last_guess=n/(double)2;
                double new_guess;
                double accuracy;
                double x;
                double absolute_value_of_x;
                x = 0;

                //while N
                while(true)
                {
                    //this is how we do the math (math is <0.000001 within range
                    //area under the curve etc etc
                    new_guess=((n/last_guess)+last_guess)/(double)2;
                    accuracy=Math.abs(new_guess-last_guess);

                    //accuracy should be close
                    if(accuracy<0.000001)
                        break;
                    last_guess=new_guess;

                    //dealing with the absolute value of x
                    if (x >=0) {
                        absolute_value_of_x = x;
                    }
                    else {
                        absolute_value_of_x = -x;
                    }
                }



                //printing out the results
                System.out.println("Newton(200.0)="+new_guess);
                System.out.println("Math.sqrt="+Math.sqrt(n));
                }
    }