Step-by-step explanation:
On the first pass, you know ...
- g = 80° . . . vertical angles
- I = 110° . . . vertical angles
- m = 20° . . . alternate interior angles (WX║ZY)
Then on the second pass, you can figure ...
- f = h = 180° -80° = 100° . . . linear angles
- j = k = 180° -110° = 70° . . . linear angles
- b = n = 180° -110° -m = 50° . . . sum of angles of a triangle
And the remaining angles can be determined using external angle and sum-of-angle relationships.
- a = o = h -70° = 30°
- c = 80° -b = 30°
- d = 360° -80° -20° -I = 150°
- L = c - m = 10° . . . c and L+m are alternate interior angles
- e = L +70° or 110° - o = 80°