? I need help please

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?

What is the equation of a line that passes through points (0, 4) and (-4,-8)?

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?