T=(({{-4, 1, 0, 0}, {-2, 0, 1, 0}, {0, 0, 0, 1}}))
Q=(({{-4, -2, 0}, {1, 0, 0}, {0, 1, 0}, {0, 0, 1}}))
A=(({{1, 4, 2, 0}, {4, 25, 26, 9}, {2, 26, 44, 34}, {0, 9, 34, 89}}))
q=(({{6}, {0}, {0}, {0}}))
b=(({{6}, {51}, {94}, {171}}))
T . A . Q // 
      MatrixForm

T=(({{-4, 1, 0, 0}, {-2, 0, 1, 0}, {0, 0, 0, 1}}))
Q=(({{-4, -2, 0}, {1, 0, 0}, {0, 1, 0}, {0, 0, 1}}))
A=(({{1, 4, 2, 0}, {4, 25, 26, 9}, {2, 26, 44, 34}, {0, 9, 34, 89}}))
q=(({{6}, {0}, {0}, {0}}))
b=(({{6}, {51}, {94}, {171}}))
T . b // 
      MatrixForm

T=(({{-4, 1, 0, 0}, {-2, 0, 1, 0}, {0, 0, 0, 1}}))
Q=(({{-4, -2, 0}, {1, 0, 0}, {0, 1, 0}, {0, 0, 1}}))
A=(({{1, 4, 2, 0}, {4, 25, 26, 9}, {2, 26, 44, 34}, {0, 9, 34, 89}}))
q=(({{6}, {0}, {0}, {0}}))
b=(({{6}, {51}, {94}, {171}}))
T . A . q // 
      MatrixForm