X + y + z = -6 -2x – 2y – 2z = 12 5x + 5y + 5z = -30 find x y and z 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?

Need asap. solve for the following inequality

Urgentwhat is the area of the figure?