我想请问下大佬这里为什么没输出

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace 九江职业技术学院
{
    class 作业5
    {
        public struct Tixin
        {
            public float shangDi;
            public float xiaDi;
            public float gao;
            public Tixin(float x,float y,float h)
            {
                shangDi = x;
                xiaDi = y;
                gao = h;
            }
            public float Arce()
            {
                return (shangDi + xiaDi) * gao / 2;
            }
        }
        static void Main(string[] args)
        {
            Tixin tixin = new Tixin(2, 8, 10);
            Console.WriteLine("梯形的面积S=", +tixin.Arce());
            Console.ReadLine();
        }
    }
}

Console.WriteLine("梯形的面积S=", +tixin.Arce());

了解下Console.WriteLine的用法

要么用占位符 Console.WriteLine("梯形的面积S={0}", tixin.Arce());

要么用字符串相加的方法，去掉逗号   Console.WriteLine("梯形的面积S="+tixin.Arce());