Answer:
75°
Step-by-step explanation:
For a straight line, all the angles on it add up to 180 degrees. So on the line where it has 155 degrees, the other angle is 25 degrees because 155 + x =180, x = 25. The angles of a triangle add up to 180 degrees, so know we have 80 + 25 + x = 180, x = 75°
