Answered

QUICK CHECK

Representing a Linear System:

[tex]\[
\begin{array}{l}
3x + 7y = 20 \\
x - 4y = 9
\end{array}
\][/tex]

Identify the values for the elements in the coefficient matrix:

[tex]\[
\begin{array}{l}
A = \left[\begin{array}{ll}
a_{11} & a_{12} \\
a_{21} & a_{22}
\end{array}\right] \\
a_{11} = 3 \\
a_{12} = 7 \\
a_{21} = 1 \\
a_{22} = -4
\end{array}
\][/tex]

Identify the values for the elements in the augmented matrix:

[tex]\[
\begin{array}{l}
\left[\begin{array}{lll}
a_{11} & a_{12} & a_{13} \\
a_{21} & a_{22} & a_{23}
\end{array}\right] \\
a_{11} = 3 \\
a_{12} = 7 \\
a_{13} = 20 \\
a_{21} = 1 \\
a_{22} = -4 \\
a_{23} = 9
\end{array}
\][/tex]



Answer :

Certainly! Let's analyze the given linear system of equations and identify the corresponding elements in the coefficient and augmented matrices.

Given system of equations:
[tex]\[ \begin{array}{l} 3x + 7y = 20 \\ x - 4y = 9 \end{array} \][/tex]

### Coefficient Matrix [tex]\( A \)[/tex]
First, we need to identify the values of the coefficient matrix elements. Each element [tex]\(a_{ij}\)[/tex] represents the coefficient of the variables [tex]\( x \)[/tex] and [tex]\( y \)[/tex] in the equations.

[tex]\[ A = \begin{bmatrix} a_{11} & a_{12} \\ a_{21} & a_{22} \end{bmatrix} \][/tex]

From the first equation [tex]\( 3x + 7y = 20 \)[/tex]:
- [tex]\(a_{11} = 3\)[/tex]
- [tex]\(a_{12} = 7\)[/tex]

From the second equation [tex]\( x - 4y = 9 \)[/tex]:
- [tex]\(a_{21} = 1\)[/tex]
- [tex]\(a_{22} = -4\)[/tex]

Thus, the coefficient matrix [tex]\( A \)[/tex] is:
[tex]\[ A = \begin{bmatrix} 3 & 7 \\ 1 & -4 \end{bmatrix} \][/tex]

### Augmented Matrix
Next, we want to identify the values of the augmented matrix elements. The augmented matrix includes the coefficients and the constants from the right-hand side of the equations.

The augmented matrix is:
[tex]\[ \left[ \begin{array}{ccc} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \end{array} \right] \][/tex]

From the first equation [tex]\( 3x + 7y = 20 \)[/tex]:
- [tex]\(a_{11} = 3\)[/tex]
- [tex]\(a_{12} = 7\)[/tex]
- [tex]\(a_{13} = 20\)[/tex] (the constant on the right-hand side)

From the second equation [tex]\( x - 4y = 9 \)[/tex]:
- [tex]\(a_{21} = 1\)[/tex]
- [tex]\(a_{22} = -4\)[/tex]
- [tex]\(a_{23} = 9\)[/tex] (the constant on the right-hand side)

Thus, the augmented matrix is:
[tex]\[ \left[ \begin{array}{ccc} 3 & 7 & 20 \\ 1 & -4 & 9 \end{array} \right] \][/tex]

### Summary
Let's summarize the computed values:

Coefficient Matrix:
[tex]\[ A = \begin{bmatrix} 3 & 7 \\ 1 & -4 \end{bmatrix} \][/tex]

Augmented Matrix:
[tex]\[ \left[ \begin{array}{ccc} 3 & 7 & 20 \\ 1 & -4 & 9 \end{array} \right] \][/tex]

Identifying each element:

- [tex]\(a_{11} = 3\)[/tex]
- [tex]\(a_{12} = 7\)[/tex]
- [tex]\(a_{13} = 20\)[/tex]
- [tex]\(a_{21} = 1\)[/tex]
- [tex]\(a_{22} = -4\)[/tex]
- [tex]\(a_{23} = 9\)[/tex]

These values provide a complete representation of the boundaries of the given linear system of equations in terms of its coefficient and augmented matrices.