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The sum of a number and its additive inverse is zero.

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$\"\"$ (Subtract 1.5 from each side)

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

The product of a number and its multiplicative inverse is one.

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$\"\"$ (Divide each side by 1.5)

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

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