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

The equation is $\"\"$ .

Apply addition property of equality: Add 8 to each side.

$\"\"$

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

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

$\"\"$ (Add: 20 + 8 = 28) $\"\"$

Apply division property of equality: Divide each side by negative 4.

$\"\"$

$\"\"$ (Cancel common terms)

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

The value of c is $\"\"$ .