using System;

public class Program

{

    public static void Main()

    {

        // get a value of x from the user.

        Console.WriteLine("Enter a value for x");

        Double x = Convert.ToDouble(Console.ReadLine());

        // calculate f(x)

        Double y = Math.Pow(x, 4.0) + Math.Pow(x, 3.0) - Math.Pow(x, 2.0) * 7 - x + 6;

        // check if f(x) = 0 ==> if x is a root of f(x)

        if(y == 0)

            Console.WriteLine(" The Value " + x + " IS a root of the equation.");

        else

            Console.WriteLine(" The Value " + x + " IS NOT a root of the equation.");

    }

}