hello!
Your answer is 150°
the 30° angle and ∠1 are a linear pair, and are supplementary. therefore they add up to 180°
take the 30°, subtract it from 180°, and you get 150°
equation:
∠1 + 30° = 180°
subtract 30 from both sides and you get 150°
I hope this helps, and have a nice day!
