How do you do this algebra question

Shiny white dental insurance costs $258 per year. approximately one-third of insured people need a filling, which averages $110 each. 80% of insured people get a preventive check-up each year, and the average cost of this visit is $95. if you consider shiny white’s income and expenses, what is the expected value of each insured customer?

If 3x+8=3x+8 is it one solution or no solution

If value of cos330° is √3/2 then find tan165°.