For a walk-a-thon a sponsor committed to give you a flat fee of $5 plus $2 for every mile m you walk. Write an expression for the total amount you will collect from your sponsor at the end of the walk-a-thon.

Lin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. she knows that the total cost to download 3 videos was $12. her work to find the equation is shown below. joylin’s work step 1 k= 3/12= 0.25 step 2 y= 0.25x where did joylin make her first error?