solving using matricies

[bailey07]

x-4y+5z=39
2x+y+z=6
-4x+3y-2z=-37


the matricies i got are:

1 -4 5 39
2 1 1 6
-4 3 -2 -37
(multiply 1st row by -2)

-2 8 -10 78
0 -3 6 45
-4 3 -2 -37

-2 -8 -10 78
0 -3 6 45
0 19 -22 119


-2 -8 -10 78
0 1 -2 15
0 19 -22 119

-2 -8 -10 78
0 8 16 120
0 19 -22 119


...where do i go from there...please help!!

 

[stapel]

-2 -8 -10 78
0 8 16 120
0 19 -22 119

I didn't check your math but, assuming the above is correct, I'd divide R[sub:2i4emlfv]1[/sub:2i4emlfv] by -2 and R[sub:2i4emlfv]2[/sub:2i4emlfv] by 8. This will "finish" column 1, and will put you in good stead to use R[sub:2i4emlfv]2[/sub:2i4emlfv] to clear out column 2 in R[sub:2i4emlfv]1[/sub:2i4emlfv] and R[sub:2i4emlfv]3[/sub:2i4emlfv]. :wink:

Eliz.