Question

Solve the system of equations 2, x, minus, 2, y, equals, 02x−2y=0 and minus, 5, x, plus, 7, y, equals, minus, 12−5x+7y=−12 by combining the equations.
Below, two sets of the two equations are shown. The first set has input boxes in front of each equation to put a number to multiply it by. When you enter a number, the corresponding equation below changes to be the result of the multiplication. Under the second set, a resulting equation is shown with input boxes for the coefficients and constant. Then, there is a "try" button. When you press the try button, if your answer is correct, it will be placed on the page and a new question will appear with a new input box. This process will continue until the final answer area appears with the submit button.
2
222222222222222 left parenthesis, 2, x(2x minus, 2, y−2y equals= 0, right parenthesis0)
-5
-5-5-5-5-5-5-5-5-5-5-5-5-5-5-5 left parenthesis, minus, 5, x(−5x plus, 7, y+7y equals= minus, 12, right parenthesis−12)
4, x4x minus, 4, y−4y equals= 00
25, x25x minus, 35, y−35y equals= 6060
xx plus+
yy equals=

Answers

Answered by GPT-4o mini
To solve the system of equations by combining them, we start with the given equations:

1. \( 2x - 2y = 0 \)
2. \( -5x + 7y = -12 \)

### Step 1: Multiply the equations

We'll multiply the first equation by \( 2.5 \) so that the coefficient of \( x \) in the first equation matches the coefficient of \( x \) in the second equation.

**Multiplying the first equation by \( 2.5 \)**:

\[
2.5 \times (2x - 2y) = 2.5 \times 0
\]

Calculating this gives:

\[
5x - 5y = 0
\]

### New system of equations:

1. \( 5x - 5y = 0 \) (new version of first equation)
2. \( -5x + 7y = -12 \)

### Step 2: Add the equations

Now we can add the two equations together:

\[
(5x - 5y) + (-5x + 7y) = 0 + (-12)
\]

This simplifies to:

\[
0 + 2y = -12
\]

### Step 3: Solve for \( y \)

\[
2y = -12
\]

Dividing by \( 2 \):

\[
y = -6
\]

### Step 4: Substitute back to find \( x \)

Now substitute \( y = -6 \) back into one of the original equations to find \( x \). We will use the first equation:

\[
2x - 2(-6) = 0
\]

This becomes:

\[
2x + 12 = 0
\]

Subtracting \( 12 \) from both sides:

\[
2x = -12
\]

Dividing by \( 2 \):

\[
x = -6
\]

### Final Solution

The solution to the system of equations is:

\[
x = -6, \quad y = -6
\]

So the final answer is:

\[
(x, y) = (-6, -6)
\]

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