Преобразования из условия эквивалентны умножению матрицы слева на матрицу
$ U = \left|
\begin{array}{cccc}
3 & -3 & -2 & -5
\\
2 & 5 & 4 & 6
\\
5 & 5 & 8 & 7
\\
4 & 4 & 5 & 6
\end{array}
\right|
(1) = (1) - (2) =>
\left|
\begin{array}{cccc}
1 & -8 & -6 & -11
\\
2 & 5 & 4 & 6
\\
5 & 5 & 8 & 7
\\
4 & 4 & 5 & 6
\end{array}
\right|
(2) = (2) - 2 * (1); (3) = (3) - 5 * (1); (4) = (4) - 4 * (1) =>
\\\\\\
\left|
\begin{array}{cccc}
1 & -8 & -6 & -11
\\
0 & 21 & 16 & 28
\\
0 & 45 & 38 & 62
\\
0 & 36 & 29 & 50
\end{array}
\right|
(3) = (3) - 2 * (2) =>
\left|
\begin{array}{cccc}
1 & -8 & -6 & -11
\\
0 & 21 & 16 & 28
\\
0 & 3 & 6 & 6
\\
0 & 36 & 29 & 50
\end{array}
\right|
=
3 *
\left|
\begin{array}{cccc}
1 & -8 & -6 & -11
\\
0 & 21 & 16 & 28
\\
0 & 1 & 2 & 2
\\
0 & 36 & 29 & 50
\end{array}
\right|
(2) <-> (3) =>
\\\\\\
-3 *
\left|
\begin{array}{cccc}
1 & -8 & -6 & -11
\\
0 & 1 & 2 & 2
\\
0 & 21 & 16 & 28
\\
0 & 36 & 29 & 50
\end{array}
\right|
(3) = (3) - 21 * (2); (4) = (4) - 36 * (2); =>
-3 *
\left|
\begin{array}{cccc}
1 & -8 & -6 & -11
\\
0 & 1 & 2 & 2
\\
0 & 0 & -26 & -14
\\
0 & 0 & -43 & -22
\end{array}
\right|
=
\\\\\\
= -3 * (-22 * (-26) - (-14 * (-43))) = 90
\\\\\\
|U * A| = |U| * |A| = 90 * 17 = 1530
$


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