$\"\"$

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

$\"\"$

$\"\"$ (Subtract $\"\"$ from both sides)

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

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

$\"\"$

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

$\"\"$ (Cancel common factors) $\"\"$ $\"\"$

$\"\"$ .