using System;

public class Program

{

    public static void Main()

    {

        double x1 = Convert.ToDouble(Console.ReadLine());

                double y1 = Convert.ToDouble(Console.ReadLine());

                double x2 = Convert.ToDouble(Console.ReadLine());

                double y2 = Convert.ToDouble(Console.ReadLine());

        double m = (y2-y1)/(x2-x1);

        double b = y1-(m*x1);

        Console.WriteLine("y = " + m + "x + " + b);

​

    }

}