$\"\"$

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The expression is $\"\"$ .

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$\"\"$ 6d + 18 = $\"\"$ d (Distributive property: $\"\"$ )

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According to Addition property of equality; if a = b than a + c = b + c.

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

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

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

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$\"\"$ (Add 5d to each side)

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$\"\"$ (Simplify)

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$\"\"$

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$\"\"$ (Divide each side by 5)

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$\"\"$ (Cancel common terms) $\"\"$

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Verify:

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

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$\"\"$

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

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$\"\"$ (Subtract: 18 $\"\"$ 15 = 3)

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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 $\"\"$ .