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

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The equation is $\"\"$ .

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$\"\"$ (Distribute 2)

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

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$\"\"$ (Distribute 3)

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

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Apply addition property of equality: Add 15 to 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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$\"\"$ (Add: $\"\"$ ) $\"\"$

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

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$\"\"$ (Subtract 2a from each side)

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

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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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$\"\"$

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$\"\"$

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Check:

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

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$\"\"$ (Substitute a = 11)

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

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

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The equality is true. $\"\"$

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The solution is $\"\"$ .