Somebody please help me

What is the slope of the line shown below?

Oscar and julie ashton are celebrating their 15th anniversary by having a reception hall. they have budgeted $4,500 for their reception. if the reception hall charges a $90 cleanup fee plus & 36 per person, find the greatest number of people that they may invite and still stay within their budget.

Which strategy is used by public health to reduce the incidence of food poisoning?