14.
y = 75, its a vertical angle to 75.
x = 75, its a vertical angle to 75, or alternate interior angle to 75.
15.
y = 74, its a supplementary angle with 106.
x = 106, its a corresponding angle to 106.
16.
y = 90, its a supplementary angle with x.
x = 90, its a corresponding angle with 90.
