$\"\"$

The statement is “ $\"\"$ ”

$\"\"$ (Substitute $\"\"$ )

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

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

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

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

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

The simplified expression is $\"\"$ .