Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
x+y+2z = 5, 2x-y+3z= 3 , 4x+y+7z= 13
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random