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Answer:
x=45°
Step-by-step explanation:
The 160° plus the unlabeled angle to the left of it are supplementary, meaning when added they equal 180°. The unlabeled angle will therefore be 20°. The angle across from the 20° will also be 20°. 115° + 20° = 135°. Now all that is left on the top half is x.
180° - 135° = 45°