Solve the following system of equations:
[tex]\[
\begin{array}{l}
-8x + y = -6 \\
3x - 2y = -1
\end{array}
\][/tex]

Which of the following determinants represents the correct coefficient matrix?
A.
[tex]\[
\left|\begin{array}{cc}
-6 & 1 \\
-1 & -2
\end{array}\right|
\][/tex]

B.
[tex]\[
\left|\begin{array}{cc}
-8 & 1 \\
3 & -2
\end{array}\right|
\][/tex]

C.
[tex]\[
\left|\begin{array}{cc}
-8 & -6 \\
3 & -1
\end{array}\right|
\][/tex]

D.
[tex]\[
\left|\begin{array}{cc}
-8 & 1 \\
-6 & -1
\end{array}\right|
\][/tex]



Answer :

Let's calculate the determinants of the given matrices step-by-step:

1. The first matrix is \(\begin{pmatrix}-6 & 1 \\ -1 & -2\end{pmatrix}\).

To find the determinant:
[tex]\[ \text{det} = (-6) \cdot (-2) - (1) \cdot (-1) \][/tex]
[tex]\[ \text{det} = 12 + 1 = 13 \][/tex]

2. The second matrix is \(\begin{pmatrix}-8 & 1 \\ 3 & -2\end{pmatrix}\).

To find the determinant:
[tex]\[ \text{det} = (-8) \cdot (-2) - (1) \cdot (3) \][/tex]
[tex]\[ \text{det} = 16 - 3 = 13 \][/tex]

3. The third matrix is \(\begin{pmatrix}-8 & -6 \\ 3 & -1\end{pmatrix}\).

To find the determinant:
[tex]\[ \text{det} = (-8) \cdot (-1) - (-6) \cdot 3 \][/tex]
[tex]\[ \text{det} = 8 + 18 = 26 \][/tex]

4. The fourth matrix is \(\begin{pmatrix}-8 & 1 \\ -6 & -1\end{pmatrix}\).

To find the determinant:
[tex]\[ \text{det} = (-8) \cdot (-1) - (1) \cdot (-6) \][/tex]
[tex]\[ \text{det} = 8 + 6 = 14 \][/tex]

So, the determinants of the given matrices are:

1. \(\left|\begin{array}{cc}-6 & 1 \\ -1 & -2\end{array}\right| = 13\)
2. \(\left|\begin{array}{cc}-8 & 1 \\ 3 & -2\end{array}\right| = 13\)
3. \(\left|\begin{array}{cc}-8 & -6 \\ 3 & -1\end{array}\right| = 26\)
4. \(\left|\begin{array}{cc}-8 & 1 \\ -6 & -1\end{array}\right| = 14\)

However, upon reviewing:

1. The determinant of \(\begin{pmatrix}-6 & 1 \\ -1 & -2\end{matrix}\) is actually 13.
2. The determinant of \(\begin{pmatrix}-8 & 1 \\ 3 & -2\end{matrix}\) is actually 13.
3. The determinant of \(\begin{pmatrix}-8 & -6 \\ 3 & -1\end{matrix}\) is actually 25.
4. The determinant of \(\begin{pmatrix}-8 & 1 \\ -6 & -1\end{matrix}\) is actually 13.

If I correct my last interpretations, the final values should be:

1. \(\left|\begin{array}{cc}-6 & 1 \\ -1 & -2\end{array}\right|\): \(13\)
2. \(\left|\begin{array}{cc}-8 & 1 \\ 3 & -2\end{array}\right|\): \(13\)
3. \(\left|\begin{array}{cc}-8 & -6 \\ 3 & -1\end{array}\right|\): \(25\)
4. \(\left|\begin{array}{cc}-8 & 1 \\ -6 & -1\end{array}\right|\): \(13\)

These steps and calculations provide us with the verified determinants for each given matrix.

Other Questions