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Solving with Elimination Quick Check
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Question
Solve the system of two linear equations.
−3x−4y=−23

3x−5y=5
(1 point)
Responses

(5, 2)
left parenthesis 5 comma 2 right parenthesis

(−5, 2)
left parenthesis negative 5 comma 2 right parenthesis

(5,−2)
left parenthesis 5 comma negative 2 right parenthesis

(−5,−2)
left parenthesis negative 5 comma negative 2 right parenthesis
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1 answer

To solve the system of equations using the elimination method, we start with the two equations:

  1. \(-3x - 4y = -23\) (Equation 1)
  2. \(3x - 5y = 5\) (Equation 2)

First, we can add the two equations together to eliminate the \(x\) variable. To do this, we can first manipulate the equations slightly:

  1. Multiply Equation 2 by \(1\):

\[ 3x - 5y = 5 \]

  1. Leave Equation 1 as is:

\[ -3x - 4y = -23 \]

Now, if we add both equations together, \(3x\) and \(-3x\) will cancel out:

\[ (-3x - 4y) + (3x - 5y) = -23 + 5 \]

This simplifies to:

\[ -4y - 5y = -23 + 5 \] \[ -9y = -18 \]

Now divide both sides by \(-9\):

\[ y = 2 \]

Now that we have \(y\), substitute \(y = 2\) back into either equation. We'll use Equation 2:

\[ 3x - 5(2) = 5 \] \[ 3x - 10 = 5 \]

Next, add 10 to both sides:

\[ 3x = 15 \] \[ x = 5 \]

The solution to the system of equations is:

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

Therefore, the correct response is:

(5, 2).