Plz help 8k-- 5k combine the like terms to create a equivalent expression

How can we find the measure of an exterior angle if we know the measurement of an interior angle

For the equations below which statement is true ?

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?