What I did for this question is I set up ans equation. 5x-7 + 3x+11 = 180 and I added the Xs and and I added 11 to -7. Then I got 8x+4=180. I then "-4" on both sides and then divided 8 by 176. Getting X as 22. We now know X and we put 22 into the equation for D which is "3x+11" getting 77 degrees. Hope this helped!
