It seems that I am missing something..

package com.codegym.task.task06.task0609;
/*
Distance between two points
*/
public class Util {
public static double getDistance(int x1, int y1, int x2, int y2) {
x1=9;
y1=12;
x2=9;
y2=12;
double a = Math.sqrt(x1);
double b = Math.sqrt(y1);
double c = Math.sqrt(x2);
double d = Math.sqrt(y2);
return b-a;
}
public static void main(String[] args) {
}
}