You sell small candles ($3 each) and large candles ($5 each) at a craft fair. You collect $84 selling a total of 20 candles. Write a system of equations to represent this scenario and solve it by substitution. How many small candles did you sell? How many large candles did you sell? PLEASE HELP

Suppose you are an avid reader and are looking to save money on the cost of books instead of paying about $20 for each book, you decide to look into purchasing a kindle for $120 you can purchase e-books for about $5 each 1. find the slope-intercept equation for the cost of the hard copy of books using x to represent the number of books 2. find the slope-intercept equation for the cost of the kindle with cost of e-books using x to represent the number of books