public void TheoryExample(double x, double y, double expected)
        {
            var math = new Mathematics();

            var result = math.Add(x, y);

            Assert.Equal(expected, result);
        }
        public void Method_add_returns_sum_of_given_doubles()
        {
            //arrange
            var math = new Mathematics();

            //act
            double result = math.Add(16.1d, 6.1d);

            //assert
            Assert.Equal(22.2, result, 2);
        }
        public void Method_add_returns_sum_of_given__integers(double x, double y, double expected)
        {
            //arrange
            var math = new Mathematics();

            //act
            double result = math.Add(x, y);

            //assert
            Assert.Equal(expected, result);
        }
        public void Add_returns_sum_of_given_values_double()
        {
            // ararange
            var math = new Mathematics();

            // act
            var result = math.Add(10, 0.5);

            //assert
            Assert.Equal(10.5, result);
        }