Please help me it is solving inequalitys

Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?

Me with this one question, and i'll upvote the brainliest answer

Acompany manufactures three types of cabinets. it makes 110 cabinets each week. in the first week, the sum of the number of type-1 cabinets and twice the number of type-2 cabinets produced was 10 more than the number of type-3 cabinets produced. the next week, the number of type-1 cabinets produced was three times more than in the first week, no type-2 cabinets were produced, and the number of type-3 cabinets produced was the same as in the previous week.