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C# C# Objects Loops and Final Touches Static Members

Posted by Ulysses Hall
Ulysses Hall
1,469 Points

Why error no "Math"

I get error that "Math" is not known. This works just fine in Visual Studio 2015

public static double CalculateHypotenuse(double sideA, double sideB) { return Math.Sqrt(Math.Pow(sideA, 2) + Math.Pow(sideB, 2));

    }
RightTriangle.cs 
namespace Treehouse.CodeChallenges
{
    class RightTriangle
    {

    }
}

1 Answer

Joshua McMahon
Joshua McMahon
6,778 Points
Joshua McMahon
Joshua McMahon
6,778 Points

It looks like everything is correct, but you haven't referenced the system namespace. Without this, the compiler doesn't know what Math.Sqrt and Math.Pow means, and is unable to proceed. As for this working in Visual Studio (if I were to hazard a guess), it is likely it attempts to reference common namespaces automatically when compiling, thus fixing some common coding mistakes.

The below code worked for me in the challenge, and I got the same error when leaving off the system namespace.

Error without System Namespace:

RightTriangle.cs(9,20): error CS0103: The name `Math' does not exist in the current context
Compilation failed: 1 error(s), 0 warnings

Solution:

using System;

namespace Treehouse.CodeChallenges
{
    class RightTriangle
    {
        public static double CalculateHypotenuse (double a, double b)
        {
            return Math.Sqrt(Math.Pow(a, 2) + Math.Pow(b, 2));
        }
    }
}
Ulysses Hall
Ulysses Hall
1,469 Points

I thought that was it, but I didn't recognize how to add the using in the challenge and tried incorrectly to put the using statement in the challenge.

I thought I had tried to say System.Math..... in my answer; but I guess I hadn't because I just tried it and it did things just fine.

Thanks.