# Example 2: The DeWright Company
with(LinearAlgebra):
# Vars: x1 x2 x3 s1m s1p s2m s2p s3m s3p (and rhs)
A:=<<0,12,5,5>|<0,9,3,7>|<0,15,4,8>|<5,1,0,0>|<0,-1,0,0>|<4,0,1,0>|<2,0,-1,0>|<0,0,0,1>|<3,0,0,-1>|<0,125,40,55>>;
#
A2:=RowOperation(A,[1,2],-5):
A3:=RowOperation(A2,[1,3],-4);
#
evalf([125/9,40/4,55/8]);
#
A4:=RowOperation(A3,4,1/8):
A5:=RowOperation(A4,[1,4],91):
A6:=RowOperation(A5,[2,4],-15):
A7:=RowOperation(A6,[3,4],-4);
#
evalf([(175/8)/(21/8), (25/2)/(5/2), (55/8)/(5/8)]);
#
A8:=RowOperation(A7,3,2/5):
A9:=RowOperation(A8,[1,3],185/8):
A10:=RowOperation(A9,[2,3],-21/8):
A11:=RowOperation(A10,[4,3],-5/8);
evalf([(35/4)/(27/20),5/(1/5)]);
#
A12:=RowOperation(A11,2,20/27):
A13:=RowOperation(A12,[1,2],15/4):
A14:=RowOperation(A13,[3,2],-1/5):
A15:=RowOperation(A14,[4,2],1/4);
evalf([(175/27)/(7/9), (145/27)/(4/9)]);
A16:=RowOperation(A15,2,9/7):
A17:=RowOperation(A16,[1,2],1/3):
A18:=RowOperation(A17,[3,2],5/9):
A19:=RowOperation(A18,[4,2],-4/9);