The vertical angles are equal to each other, that is, one of the one-sided corners will be 116°.
The sum of the one-sided angles is 180°, which means: 4x+116 = 180°
4x = 180-116 => 4x = 64°
x = 64/4 = 16°.
The sum of two adjacent angles is 180°. which means, that: 2x-3y = 180-64 = 116°
2x-3y = 116°
-2x+3y = -116
-32+3y = -116
3y = -116-(-32)
3y = -84
y = -84/3 => y = -28.