Which identity could be used to rewrite the expression X^6-27?

The variable in a relation who’s value depends on the value of the independent variable is called what?

Can someone me with this problem i don't understand i need

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?