So, first to find <em>x</em> you need to subtract 121 from 180. You do this because both the angle which measures 121 degrees and <em>x</em> lie on the same line, and since a line has an angle measure of 180, you do 180-121 to find <em>x</em>. The same thing can be done for <em>y</em>. Since the angle measure of 34 degrees and y lie on the same line you can calculate 180-34 to get <em>y. </em>So, let's do that.
180-121=x
59=x
180-34=y
146=y
Once you've done that you can easily subtract the two and get your answer.