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2x - 3y = 6 2x - 6y = 9

User Tehras
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1 Answer

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Rosie, this is the solution to the system of equations:

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2x - 3y = 6

2x - 6y = 9

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Step 1: Let's multiply by -1 the second equation, therefore we have:

2x - 3y = 6

-2x + 6y = -9

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Step 2: We eliminate x and solve for y, as follows:

-3y + 6y = 6 - 9

3y = -3

Dividing by 3 at both sides:

3y/3 = -3/3

y = -1

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Step 3: We substitute y and solve for x in the first equation, this way:

2x - 3 (-1) = 6

2x + 3 = 6

Subtracting 3 at both sides:

2x + 3 - 3 = 6 - 3

2x = 3

Dividing by 2 at both sides:

2x/2 = 3/2

x = 3/2

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Step 4: Now, let's prove x = 3/2 and y = -1 are right, replacing in the second equation, as follows:

2x - 6y = 9

2 (3/2) - 6 (-1) = 9

3 + 6 = 9

9 = 9

We proved that x = 3/2 and y = -1 are correct.

User Rochel
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3.1k points