When temperature is measured in Celsius, a reading of 0 °C means that it is cold enough to freeze water. Soren lives in Norway, and loves to ice skate on the pond near his house. When the temperature is below
0 °C, the pond is frozen and he can skate. But if the temperature rises above 0 °C, the melting ice makes
it too dangerous!

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?