How do you do these problems they are not my kind of level of math

The both equations should equal 180° when combined. So when you add like-terms you get 8x+20=180. X=20°

Since I can really only see number 50, I'll do that one. Since the 3x + 17 and 5x + 3 form a straight line, and you know that a straight line is 180 degrees, you set 3x + 17 and 5x + 3 EQUAL to the 180, set up like this: 3x + 17 + 5x + 3 = 180. Add your like terms on the left side, which gives you 8x + 20 = 180. Then, subtract the 20 from 180, that being 8x = 160. Finally, divide 8 from 160 to get x by itself. Your final answer should be x = 20.