To determine [tex]\( D_y \)[/tex] for this system of equations:

[tex]\[
\begin{array}{l}
2x - 3y = 17 \\
5x + 4y = 8
\end{array}
\][/tex]

Which determinant of the matrices below needs to be found?

A. [tex]\(\left[\begin{array}{cc}
2 & -3 \\
5 & 4
\end{array}\right]\)[/tex]

B. [tex]\(\left[\begin{array}{cc}
17 & -3 \\
8 & 4
\end{array}\right]\)[/tex]

C. [tex]\(\left[\begin{array}{cc}
2 & 17 \\
5 & 8
\end{array}\right]\)[/tex]

D. None

Answer: [tex]\(\square\)[/tex]



Answer :

To determine [tex]\( D_y \)[/tex] for the given system of equations, we start by identifying what [tex]\( D_y \)[/tex] represents in the context of solving the system using determinants.

The system of equations provided is:
[tex]\[ \begin{array}{l} 2x - 3y = 17 \\ 5x + 4y = 8 \end{array} \][/tex]

When solving a system of linear equations using Cramer's Rule, [tex]\( D_y \)[/tex] is the determinant of the matrix formed by replacing the [tex]\( y \)[/tex]-column of the coefficient matrix with the constant terms from the equations.

1. The coefficient matrix for the given system is:
[tex]\[ \left[ \begin{array}{cc} 2 & -3 \\ 5 & 4 \end{array} \right] \][/tex]

2. The constants from the right-hand side of the equations are:
[tex]\[ \left[ \begin{array}{c} 17 \\ 8 \end{array} \right] \][/tex]

3. To find [tex]\( D_y \)[/tex], we replace the [tex]\( y \)[/tex]-column (the second column) in the original coefficient matrix with the constant terms:
[tex]\[ \left[ \begin{array}{cc} 2 & -3 \\ 5 & 4 \end{array} \right] \rightarrow \left[ \begin{array}{cc} 17 & -3 \\ 8 & 4 \end{array} \right] \][/tex]

Therefore, the determinant of the matrix we need to find to determine [tex]\( D_y \)[/tex] is that of the matrix:
[tex]\[ \left[ \begin{array}{cc} 17 & -3 \\ 8 & 4 \end{array} \right] \][/tex]

So the correct option is:
[tex]\[ \boxed{B} \][/tex]