>> Hw4_Sol_MATLAB
Problem 6... 

A =
       1              2              3              4              5       
      11              8             12             10             13       
      15             14             13             12             11       
      -2             -3             -4             -5             -6       
A =
       1              2              3              4              5       
       0            -14            -21            -34            -42       
       0            -16            -32            -48            -64       
       0              1              2              3              4       
A =
       1              2              3              4              5       
       0              1              2              3              4       
       0            -16            -32            -48            -64       
       0            -14            -21            -34            -42       
A =
       1              0             -1             -2             -3       
       0              1              2              3              4       
       0              0              0              0              0       
       0              0              7              8             14       
A =
       1              0             -1             -2             -3       
       0              1              2              3              4       
       0              0              1              8/7            2       
       0              0              0              0              0       
A =
       1              0              0             -6/7           -1       
       0              1              0              5/7            0       
       0              0              1              8/7            2       
       0              0              0              0              0       
Arref =
       1              0              0             -6/7           -1       
       0              1              0              5/7            0       
       0              0              1              8/7            2       
       0              0              0              0              0       

Problem 7... 

Exercise number (1-14)? 12
A =
       1              0             -1             -1              0             40       
       1              1              0              0              0            200       
       0              1              1              0             -1            100       
       0              0              0              1              1             60       
ans =
       1              0             -1              0              1            100       
       0              1              1              0             -1            100       
       0              0              0              1              1             60       
       0              0              0              0              0              0