I need help quick please ​

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

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?

Given: ∆mop p∆mop =12+4 3 m∠p = 90°, m∠m = 60° find: mp, mo