The equation a=1/2(b1÷b2)h can be used to determine the area, a, of a trapezoid with height, h, and base lengths, b1 and b2 .which are equivalent equations? check all that apply.

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?