$\"\"$

The expression is $\"\"$ .

$\"\"$ (Write $\"\"$ )

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

$\"\"$ (The product of two same signs is positive) $\"\"$

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

$\"\"$ (The product of two different signs is negative) $\"\"$

The solution is $\"\"$ .