$\"\"$

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

$\"\"$

$\"\"$ (Subtract 1.5 from both sides)

$\"\"$ (Subtract, $\"\"$ )

$\"\"$

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

$\"\"$

$\"\"$ (Divide each side by - 10)

$\"\"$ (Cancel common factors)

$\"\"$

$\"\"$ .