mathmatrix
posted by Veronica on .
solve using the gaussjordan method.
x2y+4z=7
x+3yz=1
2x+y=2
*I get through the first two columbs, but can't get the third one to the one and zero.

http://www.irs.gov/pub/irspdf/i1040tt.pdf
Step 2: Enter the values for your matrix, and press the "Solve" button.
three rows, four columns
Input
+1 2 +4 +7
1 +3 1 1
+2 +1 +0 2
Add (1 * row1) to row2
1 2 4 7
0 1 3 6
2 1 0 2
Add (2 * row1) to row3
1 2 4 7
0 1 3 6
0 5 8 16
Add (5 * row2) to row3
1 2 4 7
0 1 3 6
0 0 23 46
Divide row3 by 23
1 2 4 7
0 1 3 6
0 0 1 2
Add (3 * row3) to row2
1 2 4 7
0 1 0 0
0 0 1 2
Add (4 * row3) to row1
1 2 0 1
0 1 0 0
0 0 1 2
Add (2 * row2) to row1
1 0 0 1
0 1 0 0
0 0 1 2 

thanks, wasn't too sure whether I could divide by 23 or not. Found the website, was really helpfull =)