$\"\"$

\

The expression is $\"\"$ .

\

$\"\"$ (Write the equation)

\

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

\

$\"\"$ (Multiply: $\"\"$ )

\

$\"\"$ (Subtract 12 from each side)

\

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

\

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

\

$\"\"$ (Divide each side by $\"\"$ )

\

$\"\"$ (Cancel common terms)

\

$\"\"$ (Divide: $\"\"$ )

\

The solution is $\"\"$ . $\"\"$

\

Check:

\

Substitute $\"\"$ in the equation.

\

$\"\"$ (Write the equation)

\

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

\

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

\

$\"\"$ (Multiply: $\"\"$ )

\

The solution was checked. $\"\"$

\

The solution is $\"\"$ .