Use the substitution method to solve the system x=y−4

𝑥
=
𝑦

4
, x+8y=2
𝑥
+
8
𝑦
=
2
.(1 point)
Responses

no solution
no solution

infinite solutions
infinite solutions

(2/3,−3/13)
(
2
3
,

3
1
3
)
left parenthesis Start Fraction 2 over 3 End Fraction comma negative 3 Start Fraction 1 over 3 End Fraction right parenthesis

(−3/13,2/3)

1 answer

To solve the system of equations using the substitution method, we have:

  1. \( x = y - 4 \)
  2. \( x + 8y = 2 \)

We will substitute the expression for \( x \) from the first equation into the second equation.

Step 1: Substitute \( x \) into the second equation.

Substituting \( x = y - 4 \) into \( x + 8y = 2 \):

\[ (y - 4) + 8y = 2 \]

Step 2: Simplify and solve for \( y \).

Combine like terms:

\[ y - 4 + 8y = 2 \ 9y - 4 = 2 \]

Now, add 4 to both sides:

\[ 9y = 2 + 4 \ 9y = 6 \]

Now, divide both sides by 9:

\[ y = \frac{6}{9} = \frac{2}{3} \]

Step 3: Substitute back to find \( x \).

Now that we have \( y \), we substitute it back into the first equation to find \( x \):

\[ x = y - 4 \ x = \frac{2}{3} - 4 \]

To subtract, convert 4 to a fraction:

\[ x = \frac{2}{3} - \frac{12}{3} = \frac{2 - 12}{3} = \frac{-10}{3} \]

Step 4: Write the solution.

Thus, the solution to the system is:

\[ (x, y) = \left( -\frac{10}{3}, \frac{2}{3} \right) \]

Looking at the response options provided, none of them match \( \left( -\frac{10}{3}, \frac{2}{3} \right) \).

It seems like the correct answer isn't listed in your provided options. Based on the calculations, you have:

The solution is:

\[ \boxed{\left( -\frac{10}{3}, \frac{2}{3} \right)} \]