Amanager received an invoice for $86.30 for 30gal ice cream. how much did each gallon cost? a $3.49 b $3.15 c $4.26 d $2.88

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?