Questions: Consider the following system of two linear equations:
3x - 2y = 12
3x + 2y = 0
Select the graph that correctly displays this system of equations and point of intersection.
Transcript text: Consider the following system of two linear equations:
\[
\begin{array}{l}
3 x-2 y=12 \\
3 x+2 y=0
\end{array}
\]
Select the graph that correctly displays this system of equations and point of intersection.
Solution
Solution Steps
Step 1: Formulate the System of Equations
We start with the given system of linear equations:
\[
\begin{array}{l}
3x - 2y = 12 \\
3x + 2y = 0
\end{array}
\]
Step 2: Represent the System in Matrix Form
The system can be represented in augmented matrix form \( [A | b] \):
\[
\left[ A | b \right] = \left[ \begin{array}{ccc}
3 & -2 & 12 \\
3 & 2 & 0 \\
\end{array} \right]
\]
Step 3: Apply Gaussian Elimination
We perform Gaussian elimination to solve the system. The steps are as follows:
Divide the first row by 3:
\[
\left[ A | b \right] = \left[ \begin{array}{ccc}
1 & -\frac{2}{3} & 4 \\
3 & 2 & 0 \\
\end{array} \right]
\]
Subtract 3 times the first row from the second row:
\[
\left[ A | b \right] = \left[ \begin{array}{ccc}
1 & -\frac{2}{3} & 4 \\
0 & 4 & -12 \\
\end{array} \right]
\]
Divide the second row by 4:
\[
\left[ A | b \right] = \left[ \begin{array}{ccc}
1 & -\frac{2}{3} & 4 \\
0 & 1 & -3 \\
\end{array} \right]
\]
Substitute back to eliminate \( y \) from the first row:
\[
\left[ A | b \right] = \left[ \begin{array}{ccc}
1 & 0 & 2 \\
0 & 1 & -3 \\
\end{array} \right]
\]
Step 4: Extract the Solutions
From the final augmented matrix, we can read the solutions:
\[
x = 2, \quad y = -3
\]
Final Answer
The solution to the system of equations is:
\[
\boxed{x = 2, \, y = -3}
\]