4x Solve the system of equations using elimination.

2x + y = 9
8x - 2y = 6

(9, 2)
』x

(5, 2)
一x

(2, 9)

(2, 5)

(5, -2)

1 answer

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

  1. \( 2x + y = 9 \) (Equation 1)
  2. \( 8x - 2y = 6 \) (Equation 2)

First, we will manipulate the equations to eliminate one of the variables. Let's eliminate \(y\). To do that, we can multiply Equation 1 by 2, so that the coefficients of \(y\) in both equations will match:

\[ 2(2x + y) = 2(9) \]

This results in:

\[ 4x + 2y = 18 \quad \text{(Equation 3)} \]

Now we can rewrite our system:

  1. \( 4x + 2y = 18 \) (Equation 3)
  2. \( 8x - 2y = 6 \) (Equation 2)

Next, we will add Equation 3 and Equation 2 to eliminate \(y\):

\[ (4x + 2y) + (8x - 2y) = 18 + 6 \]

Simplifying, we get:

\[ 4x + 8x + 2y - 2y = 24 \]

This simplifies to:

\[ 12x = 24 \]

Now divide both sides by 12:

\[ x = 2 \]

Now that we have \(x\), we can substitute this value back into one of the original equations to find \(y\). Let's use Equation 1:

\[ 2(2) + y = 9 \]

This simplifies to:

\[ 4 + y = 9 \]

So,

\[ y = 9 - 4 \] \[ y = 5 \]

Thus, the solution to the system of equations is:

\[ (x, y) = (2, 5) \]

So, the correct answer is:

(2, 5)