$\"\"$ $\"\"$

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The equations are

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$\"\"$ Equation(1)

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$\"\"$ Equation(2) $\"\"$

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Multiply the second equation each side by 2 .

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$\"\"$

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$\"\"$ (Distributive property: $\"\"$ )

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$\"\"$ (Multiply: $\"\"$ )

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$\"\"$ Equation (3) (Multiply: $\"\"$ ) $\"\"$

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Since the coefficients of the y-terms are additive inverses, y-terms

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can be eliminated by adding the equations 2 and 3.

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Write the equations in column form and add the corresponding columns.

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$\"\"$

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$\"\"$ (Divide each side by 7)

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$\"\"$ (Cancel common terms)

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$\"\"$ (Divide: $\"\"$ ) $\"\"$

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Substitute $\"\"$ in Equation (1).

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$\"\"$

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$\"\"$ (Multiply: $\"\"$ )

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$\"\"$ (Subtract 4 from each side)

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$\"\"$ (Commutative property: $\"\"$ )

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$\"\"$ (Additive inverse property: $\"\"$ )

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$\"\"$ (Additive identity property: $\"\"$ )

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$\"\"$ (Subtract: $\"\"$ )

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$\"\"$

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The solution is $\"\"$ .