I made a mistake when I went over number 28 (16:03-20:17).  The formula for tangent should be tan(x+y) = (tanx + tany) / (1 - tanxtany).  The right answer should be 2 + sqrt3.  My error was in the angles that I chose to use.  I used 4pi/3 - 3pi/4 and that equals 7pi/12 not -7pi/12.  What I should have used was -pi/3 - pi/4.  I apologize for the confusion.  Everything else that I went over was correct.  The answer key is posted so you can check your answers.