$\"\"$

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The equation is $\"\"$ .

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Apply commutative property of addition: a + b = b + a.

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$\"\"$

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

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Apply subtraction property of equality: If a = b then $\"\"$ .

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$\"\"$ (Subtract 7y from each side) \ \

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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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$\"\"$ (Subtract 5 from each side)

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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 check, substitute $\"\"$ , in $\"\"$ .

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$\"\"$

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

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

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

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The solution is $\"\"$ .