Guys I'm stuck plz help

What is x and y (use substitution? ) 5x+3y=38 and y=3x+8?

Select the correct answer. in the figure, angle k measures 45°. what is the measurement of angle c? a. 38° b. 45° c. 90° d. 98°

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?