Hi there!
If the lines are parallel, Angles 1 and 2 would have to be congruent because they are corresponding angles. Therefore, to solve, all we need to do is set the values of the angles equal to each other because the angles are congruent.
WORK:
20 - 8x = 30 - 16x
-8x = 10 - 16x
8x = 10
x = 1.25
Hope this helps!! :)
If there's anything else that I can help you with, please let me know!