Riley started selling bracelets. during the first month she sold 400 bracelets at $10 each. she tried raising the price, but for every $0.50 she raised the price, she sold 8 fewer bracelets. what price should she charge in order to make the highest possible gross income?

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

Need so much on this one how many yards?

The function f(x)= -(x+5)(x+1) is down. what is the range of the function?