$\"\"$

The equation is $\"\"$ .

Apply addition property of equality: Add 7 to each side.

$\"\"$

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

$\"\"$ (Apply additive identity property: $\"\"$ )

$\"\"$ (Apply additive inverse property: $\"\"$ )

$\"\"$ (Subtract: $\"\"$ )

$\"\"$

Check:

To check the solution, substitute $\"\"$ in original equation.

$\"\"$

$\"\"$ (Product of two different signs is negative)

$\"\"$ (Subtract: $\"\"$ )

The statement is true. $\"\"$

The value is $\"\"$ .