Area of a Triangle in the Cartesian Coordinate System

/* Author: @TharieHimself */
import java.util.Scanner;
public class Triangle{
	
	public static void main(String[] args) {
		
		Triangle tri = new Triangle();
		tri.calcArea();
		
	}
	public void calcArea(){
	     Scanner scan = new Scanner(System.in);
	     
	     double[][] coordinates = new double[3][2];
	     double[] sides = new double[3];
	     int count = 0;
	     String axis;
	     
	     for(int r=0; r<3; r++)
	     {
	    	 for(int c=0; c<2;c++){
	    		 count++;
	    		 axis = (count % 2 == 0) ? "Y" : "X";
	    		 System.out.print("Enter "+axis+" Coordinate for Node "+count+": ");
	    		 coordinates[r][c] = scan.nextDouble();
	    	 }
	     }
	     
	     /* THIS PART CAN NOT BE ACHIEVED THROUGH A FOR LOOP; THERE IS NO PATTERN */ 
	     sides[0] = Math.sqrt((Math.pow((coordinates[0][0]- coordinates[1][0]), 2)) + Math.pow((coordinates[0][1] - coordinates[1][1]), 2));
	     sides[1] = Math.sqrt((Math.pow((coordinates[1][0]- coordinates[2][0]), 2)) + Math.pow((coordinates[1][1] - coordinates[2][1]), 2));
	     sides[2] = Math.sqrt((Math.pow((coordinates[2][0]- coordinates[0][0]), 2)) + Math.pow((coordinates[2][1] - coordinates[0][1]), 2));
	     
	     double s = (sides[0]+ sides[1]+ sides[2])/2;
	     double area = Math.sqrt(s*(s-sides[0])*(s-sides[1])*(s-sides[2]));
	     
	     /* THIS WILL ROUND OFF THE AREA TO THREE DECIMAL PLACES */
	     double roundOff = Math.round(area * 1000.0) / 1000.0;
	  	     
	     if(!(area > 0))
	    	 System.out.println("\nYour Triangle does not exist!");
	     else
	     System.out.println("\nArea of your Triangle is: "+roundOff);      	     
	}

}