Solve the system of equations using substitution.

[tex]\[
\begin{array}{l}
3x + 2y = 7 \\
x = 3y + 6
\end{array}
\][/tex]

A. [tex]\((0, -2)\)[/tex]

B. [tex]\((1, 2)\)[/tex]

C. [tex]\((3, -1)\)[/tex]

D. [tex]\((6, 0)\)[/tex]



Answer :

Sure! Let's solve the given system of equations using the substitution method.

The system of equations is:
[tex]\[ 3x + 2y = 7 \][/tex]
[tex]\[ x = 3y + 6 \][/tex]

Step 1: Substitute the expression for [tex]\( x \)[/tex] from the second equation into the first equation.

The second equation gives us:
[tex]\[ x = 3y + 6 \][/tex]

We substitute this expression for [tex]\( x \)[/tex] into the first equation:
[tex]\[ 3(3y + 6) + 2y = 7 \][/tex]

Step 2: Simplify the equation.

First, distribute 3 in the equation:
[tex]\[ 9y + 18 + 2y = 7 \][/tex]

Next, combine like terms:
[tex]\[ 11y + 18 = 7 \][/tex]

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

Subtract 18 from both sides of the equation:
[tex]\[ 11y = 7 - 18 \][/tex]
[tex]\[ 11y = -11 \][/tex]

Divide both sides by 11:
[tex]\[ y = -1 \][/tex]

Step 4: Substitute the value of [tex]\( y \)[/tex] back into the second equation to find [tex]\( x \)[/tex].

We already have the equation:
[tex]\[ x = 3y + 6 \][/tex]

Substitute [tex]\( y = -1 \)[/tex] into the equation:
[tex]\[ x = 3(-1) + 6 \][/tex]
[tex]\[ x = -3 + 6 \][/tex]
[tex]\[ x = 3 \][/tex]

Therefore, the solution to the system of equations is:
[tex]\[ (x, y) = (3, -1) \][/tex]

Out of the given options:
[tex]\[ \begin{array}{l} (0, -2) \\ (1, 2) \\ (3, -1) \\ (6, 0) \end{array} \][/tex]

The correct solution is:
[tex]\[ (3, -1) \][/tex]