Draw a line that contains the vertex for the 30 degree angle and the vertex for the x degree angle. Make sure that the line crosses (or ends at) the parallel lines.
Next time you need to follow the forum guidelines which states that you need to show some work or at least tell us where you are stuck. And please don't bother to ask for step by step instructions as that is not going to happen on this forum. We want you to solve your own problem with helpful hints from helpers on this forum.
Let's see how far you can get with my hint. Please post back.