In Deepak’s recipe, the relationship between teaspoons of salt (\text{t})(t)left parenthesis, start text, t, end text, right parenthesis and cups of flour (\text{c})(c)left parenthesis, start text, c, end text, right parenthesis is shown on the graph below.

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?