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

The expression is $\"\"$ .

According to multiplication property of equality: Multiply each side by 7.

$\"\"$

$\"\"$ (Cancel common terms)

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

According to division property of equality: Divide each side by negative 2.

$\"\"$

$\"\"$ (Cancel common terms)

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

Check:

Check the solution by substituting $\"\"$ in the original equation.

$\"\"$

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

The value of $\"\"$ .