hello guys i am having quite a problem trying to solve this, i am doing something wrong.
4x + 3y - 4z= -7
5x - 2y + 3z= 13
6x + 4y - 3z= -4

these were my 1st attempts, but they went wrong i know the answer should be 1 -1 2.
http://img237.imageshack.us/img237/4216/maths10001.jpg
http://img64.imageshack.us/img64/5191/maths10002.jpg

please help me =(