using System;

public class Program

{

    public static void Main()

    {

                Console.Write("A1 = "); double A1 = double.Parse(Console.ReadLine());

                Console.Write("B1 = "); double B1 = double.Parse(Console.ReadLine());

                Console.Write("C1 = "); double C1 = double.Parse(Console.ReadLine());

                Console.Write("xm = "); double xm = double.Parse(Console.ReadLine());

                Console.Write("ym = "); double ym = double.Parse(Console.ReadLine());

​

                double A2 = -(B1 / A1);

                double B2 = 1;

                double C2 = -(A2 * xm + B2 * ym);

                double xa = (C1 - B1 * C2) / (A2 * B1 - A1);

                double ya = -(A1 * xa + C1) / B1;

                double dist = Math.Sqrt((xa - xm) * (xa - xm) + (ya - ym) * (ya - ym));

                Console.WriteLine("================");

                Console.WriteLine("Разтояние: " + Math.Round(dist, 2).ToString());

                Console.Write("================");

    }

}