Find the value of X. please help? I’m having so much trouble with this one because I’m not sure if it’s 35.

Answer: 138
Step-by-step explanation:
because the line that it is lying on is flat, it has to combine with the angle that is 42 degrees to equal 180. So just subtract 42 from 180 and its 138.
Hope this helped, please give brainliest :)