Answer
x = 85°
Step-by-step explanation
The image of this question shows that the two angles 20° and (x - 15)° both sum up to give a right angle (90°). So,
20° + (x - 15)° = 90°
20° + x - 15° = 90°
x° + 20° - 15° = 90°
x + 5° = 90°
x = 90° - 5°
x = 85°
Hope this Helps!!!