please tell me how to solve this

Answer: 55 = x
Step-by-step explanation:
a line is 180'
so all you do is
180 - 125 = x
the 35 and 90' is to throw you off
55 = x
Answer:
x=55
Step-by-step explanation:
Angles on a straight line add up to 180 degrees
Angle 35, 90(the box) and x are all on a straight line
35 + 90=125
180-125=55
x=55