Solve the system of equations using any method.

[tex]\[
\begin{array}{l}
x + 4y = 13 \\
2x + 3y = 6
\end{array}
\][/tex]

A. [tex]\((3, 5)\)[/tex]
B. [tex]\((-4, 5)\)[/tex]
C. [tex]\((-3, 4)\)[/tex]
D. No solution
E. Infinitely many solutions



Answer :

To solve the system of equations:

[tex]\[ \begin{array}{l} x + 4y = 13 \\ 2x + 3y = 6 \end{array} \][/tex]

we will use one of the methods typically employed for solving systems of linear equations, such as substitution, elimination, or matrix methods. Here, I'll describe the process clearly.

### Method: Elimination

Step 1: Multiply the equations to make the coefficients of x (or y) the same in both equations, thereby allowing us to eliminate one of the variables.

Let's start by aligning the coefficients of [tex]\(x\)[/tex].

- Multiply the first equation by 2:
[tex]\[ 2(x + 4y) = 2(13) \][/tex]
[tex]\[ 2x + 8y = 26 \][/tex]

Now we have:
[tex]\[ 2x + 8y = 26 \quad \text{(Equation 3)} \][/tex]
[tex]\[ 2x + 3y = 6 \quad \text{(Equation 2)} \][/tex]

Step 2: Subtract Equation 2 from Equation 3 to eliminate [tex]\(x\)[/tex]:

[tex]\[ (2x + 8y) - (2x + 3y) = 26 - 6 \][/tex]
[tex]\[ 2x + 8y - 2x - 3y = 20 \][/tex]
[tex]\[ 5y = 20 \][/tex]
[tex]\[ y = \frac{20}{5} \][/tex]
[tex]\[ y = 4 \][/tex]

Step 3: Substitute [tex]\(y = 4\)[/tex] back into one of the original equations to solve for [tex]\(x\)[/tex]. We'll use the first equation:

[tex]\[ x + 4(4) = 13 \][/tex]
[tex]\[ x + 16 = 13 \][/tex]
[tex]\[ x = 13 - 16 \][/tex]
[tex]\[ x = -3 \][/tex]

So, the solution to the system of equations is [tex]\(x = -3\)[/tex] and [tex]\(y = 4\)[/tex]. This gives us the point [tex]\((-3, 4)\)[/tex].

Step 4: Check the solution against the multiple choice answers:

1. [tex]\((3, 5)\)[/tex]
2. [tex]\((-4, 5)\)[/tex]
3. [tex]\((-3, 4)\)[/tex]
4. No solution
5. Infinitely many solutions

Our solution [tex]\((-3, 4)\)[/tex] matches option 3.

Therefore, the final answer is:

[tex]\[ \boxed{3} \][/tex]

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