The area of a rectangle is 1.7 square units. the length is 3.4 units and the width is z units. what is the value of z? z=0.5 z=2 z=5.1 z=5.78

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?