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Mp model with mathematics explain how the number of text messages dario sent and the cost form an arithmetic sequence.then write an expression to find dario's text messaging bill if he sends n text messages over 250.

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

Sophia wrote an equation to represent the revenue of a movie theater for one day. she let x represent the number of child tickets sold and y represents the nunver of adult tickets sold. if a child ticket cost $4, an adult ticket cost $6, and the total revenue for the daybwas $420, which equation could sophia use to represent the number of chikd and adult tickets that were sold?