Please help I don't understand this

2y= 3 2 x−2 y = − 1 3 x + 1 y=− 3 1 x+1

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?

Use composition to determine if (x) or h(x) is the inverse of f(x) for the limited domain x2-1.