Linear or non linear help

Sarah took the advertising department from her company on a round trip to meet with a potential client. including sarah a total of 11 people took the trip. she was able to purchase coach tickets for $280 and first class tickets for $1280. she used her total budget for airfare for the trip, which was $6080. how many first class tickets did she buy? how many coach tickets did she buy?

Asap! i need this done today and i really don’t understand it. some one ! will mark

Marking brainliest for original answer.. are these two triangles similar? how can you tell?