Answer:
Z = 1°
Explanation:
Since the shape is a triangle it means that all it's interior angles sum to 180°
To find the missing angle sum up the known angles and subtract them from 180°
That's
X +
Y +
Z = 180°
89° + 90° +
Z = 180°
Z = 180 - 179°
We have the final answer as
Z = 1°
Hope this helps you