The relationship between a and b if a+b=0

Is the power produced directly proportional to the wind speed, give reasons for your answer?

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?

Find the solution on the interval [0, 2pi)