$\"\"$ $\"\"$

The equation is $\"\"$ .

Apply addition property of equality: Add 4 to each side.

$\"\"$

Apply commutative property of addition: a + b = b + a.

$\"\"$

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

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

Check:

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

$\"\"$

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

The equation is true. $\"\"$

The value of $\"\"$ .