When x=12, y=8. Find x when y=12

For what values of x is x2 + 2x = 24 true?

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 the elimination method to solve the systems of equations.choose the correct ordered pair. 7x+4y=39