$\"\"$

The equation is $\"\"$ .

Apply subtraction property of equality: Subtract 7 from each side.

$\"\"$

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

$\"\"$

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

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

Apply division property of equality: Divide each side by 3.

$\"\"$

$\"\"$ (Cancel common terms) $\"\"$

Check:

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

$\"\"$

$\"\"$ (Cancel common terms)

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

The equality is true. $\"\"$

The value of $\"\"$ .