Is Hugo's solution to the system of equations correct? Explain why or why not.

[tex]\[
\begin{array}{l}
2x - 3y = -11 \\
3x + 2y = -5
\end{array}
\][/tex]

\begin{tabular}{|l|l|}
\hline
Step 1 &
\begin{tabular}{l}
[tex]$4x - 6y = -22$[/tex] \\
[tex]$9x + 6y = -15$[/tex]
\end{tabular} \\
\hline
Step 2 & [tex]$13x = -37$[/tex] \\
\hline
Step 3 & [tex]$x = -\frac{37}{13}$[/tex] \\
\hline
Step 4 &
\begin{tabular}{r}
[tex]$3\left(-\frac{37}{13}\right) + 2y = -5$[/tex] \\
[tex]$-\frac{111}{13} + 2y = -5$[/tex] \\
[tex]$2y = \frac{66}{13}$[/tex] \\
\end{tabular} \\
& [tex]$y = \frac{33}{13}$[/tex] \\
\hline
Step 5 & The solution is [tex]$\left(-\frac{37}{13}, \frac{33}{13}\right)$[/tex] \\
\hline
\end{tabular}



Answer :

To determine whether Hugo's solution to the given system of equations is correct, we will need to solve the system step-by-step and then compare it with Hugo’s solution. The provided system is:

[tex]\[ \begin{cases} 2x - 3y = -11 \\ 3x + 2y = -5 \end{cases} \][/tex]

Step 1: Let's use the method of elimination to solve the system. First, we need to align the coefficients for one of the variables (let’s choose [tex]\(y\)[/tex]) so that we can eliminate one variable.

Multiply the first equation by 2 and the second equation by 3:

[tex]\[ \begin{cases} 4x - 6y = -22 \quad \text{(Equation 1 multiplied by 2)} \\ 9x + 6y = -15 \quad \text{(Equation 2 multiplied by 3)} \end{cases} \][/tex]

Step 2: Now, add both equations to eliminate [tex]\(y\)[/tex]:

[tex]\[ 4x - 6y + 9x + 6y = -22 - 15 \][/tex]

This simplifies to:

[tex]\[ 13x = -37 \][/tex]

Step 3: Solve for [tex]\(x\)[/tex]:

[tex]\[ x = -\frac{37}{13} \][/tex]

Step 4: Substitute [tex]\(x = -\frac{37}{13}\)[/tex] back into one of the original equations to solve for [tex]\(y\)[/tex]. We will use the first equation [tex]\(2x - 3y = -11\)[/tex]:

[tex]\[ 2\left(-\frac{37}{13}\right) - 3y = -11 \][/tex]

Simplify:

[tex]\[ -\frac{74}{13} - 3y = -11 \][/tex]

Convert [tex]\(-11\)[/tex] to a fraction with the same denominator:

[tex]\[ -\frac{74}{13} - 3y = -\frac{143}{13} \][/tex]

Isolate [tex]\(3y\)[/tex]:

[tex]\[ -3y = -\frac{143}{13} + \frac{74}{13} \][/tex]

[tex]\[ -3y = -\frac{69}{13} \][/tex]

[tex]\[ y = \frac{69}{39} \][/tex]

[tex]\[ y = \frac{23}{13} \][/tex]

So, the solution we obtain is:

[tex]\[ x = -\frac{37}{13}, \quad y = \frac{23}{13} \][/tex]

Step 5: Compare this solution to Hugo's solution, which was [tex]\(x = -2\)[/tex] and [tex]\(y = \frac{1}{2}\)[/tex]. Clearly, our solutions do not match Hugo's.

Conclusion:
Hugo's solution is incorrect. The correct solution is [tex]\(x = -\frac{37}{13}\)[/tex] and [tex]\(y = \frac{23}{13}\)[/tex].