Grace has xx pennies and yy nickels. She has at least 20 coins worth a maximum of $0.40 combined. Solve this system of inequalities graphically and determine one possible solution.

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?