Online tools for Gaussian elimination / LU decomposition ?

[XodoX]

I can not find any useful online tool that solves you a system of equations using Gaussian elimination and LU decomposition. So just a system like:

-3X+4X+9X+4x=-2
9X+2X+1X-5X=2

etc. Just about 4 lines.

several lines. So basically an online tool where you can just plug in the -3,4,9,4,-2 etc and it solves it for you. Same with the LU decomposition for systems like this one.

And, does somebody know of a website where Gaussian elimination and LU explained in detail ? I know how to do Gaussian elimination, but I'm used to do it in a different way. Solve the equations for whatever, but I'm talking about just taking the numbers, put them in a matrix and then solve it. I'm not quite sure how that works. LU decomposition is tricky too, imo. Just can't find anything that's useful. I would appreciate any help!

 

[bangthatdrum]

http://tutorial.math.lamar.edu/Classes/LinAlg/SolvingSystemsOfEqns.aspx

i would use a MATLAB script for this.

 

[gsal]

or a python script (with numpy and scipy)...

...or, if you want something on-line, try http://www.sagemath.org/" ...again, though, you would need to know what functions to call, etc...

 

[Edgardo]

You can use wolfram alpha:
http://www.wolframalpha.com/examples/EquationSolving.html"
http://www.wolframalpha.com/input/?i=lu+decomposition"

 

[XodoX]

Thank you guys!