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

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The equation is $\"\"$ .

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$\"\"$ (Apply commutative property of addition: $\"\"$ )

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$\"\"$ (Add: 5y + 2y = 7y) $\"\"$

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Apply subtraction property of equality: Subtract 7y from each side.

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$\"\"$

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$\"\"$ (Apply additive inverse property: $\"\"$ )

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$\"\"$ (Apply additive identity property: $\"\"$ )

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$\"\"$ (Apply commutative property of addition: $\"\"$ )

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

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Apply subtraction property of equality: Subtract 5 from each side.

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$\"\"$

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$\"\"$ (Apply additive inverse property: $\"\"$ )

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$\"\"$ (Apply additive identity property: $\"\"$ )

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

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Check:

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To substitute $\"\"$ in $\"\"$ .

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$\"\"$ (Substitute $\"\"$ )

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

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

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

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

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$\"\"$ (Add: $\"\"$ )

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The equality is true $\"\"$

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The equality solution is $\"\"$ .