$\"\"$

The expression is $\"\"$ .

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

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

$\"\"$

$\"\"$ (Apply distributive property: $\"\"$ )

$\"\"$ (Add: $\"\"$ )

$\"\"$ (Apply distributive property: $\"\"$ )

$\"\"$ (Add: $\"\"$ )

$\"\"$

The simplified expression is $\"\"$ .