Running consumes about 720 calories per hour about how many are used if you run for 40 minutes

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

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab

Which is the focus of a parabola with equation y2=4x