$\"\"$

From the diagram the angles are $\"\"$ .

In a quadrilateral sum of angle measures is $\"\"$ .

$\"\"$

$\"\"$ (Combine like terms) $\"\"$

$\"\"$ (Divide each side by 4)

$\"\"$ (Cancel common terms)

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

So, the angle measures are $\"\"$ . $\"\"$

The value of x is $\"\"$ . The angle measures are $\"\"$ .