Use long division of polynomials to divide x^3+x^2-4x-4 by x-3 [express the complete quotient in the form Q+r/d.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?

The measure of angle 0 is 600 degrees

I’m really confused and need your assist me with this question i’ve never been taught