$\"\"$

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The equation is $\"\"$

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

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According to addition property of equality; if $\"\"$ , then $\"\"$ .

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$\"\"$ (Add 15 to each side)

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

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

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$\"\"$ (Divide both sides by 3)

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$\"\"$ (Cancel common terms)

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

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Verify the solution: \

To verify the solution, substitute $\"\"$ in original equation.

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$\"\"$ \ \

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

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

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Compare the values, the equation is true.

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$\"\"$

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The value of $\"\"$ .

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