The answer is 59.
All triangles add up to 180°.
Angle A= x°
Angle B= 75°
Angle C= unknown
The left side shows an outer angle, which is 134°. Together with angle C, they should make 180°. To find out what angle C is equal to, subtract 134 from 184, which is equal to 46.
Angle A= x°
Angle B= 75°
Angle C = 46°
To find out what angle A is, subtract 75 and 46 from 180, which is equal to 59.
x = 59°