Answer:
18. x = (?)
x = 60° (Alternate angles)
19. y = (?)
(y + 35°) + (60° + 55°) = 180° (supplementary angles)
y + 150° = 180°
y = 180° - 150°
y = 30°
20. z = (?)
z = 180° - y - 55°
z = 180° - 30° - 55°
z = 95°
