Answer:
y = 38°
Explanation:
If Angle x and angle y are complementary, then x + y = 90°
Also, if angle x is supplementary to a 128 angle, then x + 128° = 180°.
Solving the latter equation for x, we get x = 52°.
Therefore, by the first equation, x + y = 90° becomes 52° + y = 90°, yielding
y = 38°