Which equation does not represent y as a function of x

How far is x from 5 on a number line?

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?

The equation of line wx is y=2x-5. write an equation of a line perpendicular to line wx in slopeintercept form the contains points (-1,-2)