Quick I need some help guys

Barney & noblet customers can choose to purchase a membership for $25 per year members receive 10% off all store purchases 1. how much would a member pay per year if he bought $50 worth of items each year? 2. write a slope-intercept equation that expresses how much a member pays per year using x to represent his purchases per year 3. how much would a member have to spend per year to pay off his membership fee?

In which direction does the left side of the graph of this function point? f(x) = 3x3 - x2 + 4x - 2

What is the scale factor of axyz to auvw?