Jaylin solved this equation from the card sort: 15 – 7x= 3 + 5x
12 – 7x= 5x
12 = 12x
1= x
Is this correct?

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?