static void Main(string[] args) { StringBuilder result = new StringBuilder(); try { Triangle triangle = new Triangle(12, 7, 8); result.Append($"{triangle}\r\n"); result.Append(string.Format("Triangle perimeter: {0:0.##}\r\n", triangle.GetTrianglePerimeter())); result.Append(string.Format("Triangle square: {0:0.##}\r\n", triangle.GetTriangleSquare())); Console.WriteLine(result); } catch (ArgumentException e) { Console.WriteLine(e.Message); } Console.ReadLine(); }