Simplify. show work
9(20-3·8)-4²

thank you

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

8) during a clearance sale, a keyboard that normally sells for $49.99 is discounted for $34.99. what is the percent discount?

Find the least common factor denominator for these two rational 7/x^2 and 7/5x