IDNLearn.com makes it easy to get reliable answers from experts and enthusiasts alike. Join our platform to receive prompt and accurate responses from experienced professionals in various fields.

Which determinants can be used to solve for [tex]$x$[/tex] and [tex]$y$[/tex] in the system of linear equations below?
[tex]\[
\begin{array}{l}
-3x + 2y = -9 \\
4x - 15y = -25
\end{array}
\][/tex]

A. [tex]\[
|A|=\left|\begin{array}{cc}
-3 & 2 \\
4 & -15
\end{array}\right|,\quad
|A_x|=\left|\begin{array}{cc}
-9 & 2 \\
-25 & -15
\end{array}\right|,\quad
|A_y|=\left|\begin{array}{cc}
-3 & -9 \\
4 & -25
\end{array}\right|
\][/tex]

B. [tex]\[
|A|=\left|\begin{array}{cc}
-3 & 2 \\
4 & -15
\end{array}\right|,\quad
|A_x|=\left|\begin{array}{cc}
-3 & -9 \\
4 & -25
\end{array}\right|,\quad
|A_y|=\left|\begin{array}{cc}
-9 & 2 \\
-25 & -15
\end{array}\right|
\][/tex]

C. [tex]\[
|A|=\left|\begin{array}{c}
-9 \\
-25
\end{array}\right|,\quad
|A_x|=\left|\begin{array}{cc}
-9 & 2 \\
-25 & -15
\end{array}\right|,\quad
|A_y|=\left|\begin{array}{cc}
-3 & -9 \\
4 & -25
\end{array}\right|
\][/tex]

D. [tex]\[
|A|=|-9|,\quad
|A_{x}|=\left|\begin{array}{ll}
-3 & -9
\end{array}\right|,\quad
|A_{y}|=\left|\begin{array}{ll}
-9 & 2
\end{array}\right|
\][/tex]


Sagot :

To solve the given system of linear equations using determinants, we can employ Cramer's Rule. The system of equations is:

[tex]\[ \begin{array}{l} -3x + 2y = -9 \\ 4x - 15y = -25 \end{array} \][/tex]

According to Cramer's Rule, we solve for [tex]\(x\)[/tex] and [tex]\(y\)[/tex] using the following determinants:

1. Determinant of the Coefficient Matrix ([tex]\(|A|\)[/tex]):
[tex]\[ |A| = \left|\begin{array}{cc} -3 & 2 \\ 4 & -15 \end{array}\right| \][/tex]

2. Determinant of the Matrix for [tex]\(x\)[/tex] ([tex]\(|A_x|\)[/tex]):
[tex]\[ |A_x| = \left|\begin{array}{cc} -9 & 2 \\ -25 & -15 \end{array}\right| \][/tex]

3. Determinant of the Matrix for [tex]\(y\)[/tex] ([tex]\(|A_y|\)[/tex]):
[tex]\[ |A_y| = \left|\begin{array}{cc} -3 & -9 \\ 4 & -25 \end{array}\right| \][/tex]

Using the determinant values you provided:

[tex]\[ |A| = 37.000000000000014 \][/tex]
[tex]\[ |A_x| = 184.99999999999991 \][/tex]
[tex]\[ |A_y| = 110.99999999999997 \][/tex]

We can now form the equations for [tex]\(x\)[/tex] and [tex]\(y\)[/tex] using Cramer's Rule:

[tex]\[ x = \frac{|A_x|}{|A|} \][/tex]
[tex]\[ y = \frac{|A_y|}{|A|} \][/tex]

Substituting the calculated determinants:

[tex]\[ x = \frac{184.99999999999991}{37.000000000000014} \][/tex]
[tex]\[ y = \frac{110.99999999999997}{37.000000000000014} \][/tex]

Upon simplifying these fractions, we get:

[tex]\[ x \approx 5 \][/tex]
[tex]\[ y \approx 3 \][/tex]

Therefore, the determinants that can be used to solve for [tex]\(x\)[/tex] and [tex]\(y\)[/tex] in this system of linear equations are:

[tex]\[ |A| = \left|\begin{array}{cc} -3 & 2 \\ 4 & -15 \end{array}\right|, \quad |A_x| = \left|\begin{array}{cc} -9 & 2 \\ -25 & -15 \end{array}\right|, \quad |A_y| = \left|\begin{array}{cc} -3 & -9 \\ 4 & -25 \end{array}\right| \][/tex]