Answer: angle COS = 30 degrees
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Explanation:
Angle BPO is congruent to angle POC because they are alternate interior angles and because AB is parallel to CD. So angle POC is 120+x degrees
This adds with angle COS to get 180
(angle POC) + (angle COS) = 180
(120+x) + (x) = 180
2x+120 = 180
2x = 180-120
2x = 60
x = 60/2
x = 30
angle COS = x = 30
angle POC = 120+x = 120+30 = 150
angle BPO = angle POC = 150
