You can
put this solution on YOUR website! perform matrix row operation and write the new matrix
1 2 2 2
0 1 -1 2 -5R2+R3
0 5 4 1
-5R2+R3
-5R2 means to do this work to the side
1. Multiply row #2 by -5 : -5(0 1 -1 2) = (0 -5 5 -10)
and then +R3 means
2. Add that to row #3 : (0 -5 5 -10) + (0 5 4 1) = (0 0 9 -9)
3. Replace row #3 by (0 0 9 -9)
1 2 2 2
0 1 -1 2
0 0 9 -9
That's the new matrix.
Edwin