Please help with this

Solving algebraic equations 2m+3=11

Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.

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?