Questions: Use the Gauss-Jordan method to solve the system of equations.
15)
x-y+z=-2
x+y+z=-6
x+y-z=4
A) No solution
B) (1,-2,-5)
C) (1,-5,-2)
D) (-5,1,-2)
Transcript text: Use the Gauss-Jordan method to solve the system of equations.
15)
\[
\begin{array}{l}
x-y+z=-2 \\
x+y+z=-6 \\
x+y-z=4
\end{array}
\]
A) No solution
B) $(1,-2,-5)$
C) $(1,-5,-2)$
D) $(-5,1,-2)$
Solution
Solution Steps
To solve the system of equations using the Gauss-Jordan method, we will first represent the system as an augmented matrix. Then, we will perform row operations to transform the matrix into reduced row-echelon form (RREF). Finally, we will interpret the resulting matrix to find the solution to the system of equations.
Step 1: Formulate the Augmented Matrix
The given system of equations is:
\[
\begin{align_}
x - y + z &= -2 \\
x + y + z &= -6 \\
x + y - z &= 4
\end{align_}
\]
We can represent this system as an augmented matrix:
\[
A = \begin{bmatrix}
1 & -1 & 1 & | & -2 \\
1 & 1 & 1 & | & -6 \\
1 & 1 & -1 & | & 4
\end{bmatrix}
\]
Step 2: Perform Gauss-Jordan Elimination
By applying row operations to transform the augmented matrix into reduced row-echelon form (RREF), we obtain:
\[
\begin{bmatrix}
1 & 0 & 0 & | & 1 \\
0 & 1 & 0 & | & -2 \\
0 & 0 & 1 & | & -5
\end{bmatrix}
\]
Step 3: Extract the Solution
From the RREF, we can read the solutions directly:
\[
\begin{align_}
x &= 1 \\
y &= -2 \\
z &= -5
\end{align_}
\]
Thus, the solution to the system of equations is \( (1, -2, -5) \).