Answer:
x =15°
Explanation:
Given that the horizontal line is 90° to the vertical line, then both the angles have to necessarily add up to 90° i.e
(5x-10)° + 25° = 90°
5x - 10 + 25 = 90
5x + 15 = 90 (subtract 15 from both sides)
5x = 90 - 15
5x = 75 (divide both sides by 5)
x = 75 / 5 = 15°