DelegateMath.cs

using System;

namespace DelegateMath
{
  class Program
  {
    static void Main(string[] args)
    {
       PrintResult(Multiply, 5, 12);
    }

    delegate double Take2intReturn1int(int a, int b);

    static double Multiply(int x, int y) => x * y;

    static void PrintResult(Take2intReturn1int func, int p, int q)
      => Console.WriteLine(func(p, q));
  }
}