(-2,2) (4,20)

Find the value of x when y is 9.

I will assume you want

(-2,2) , (x,9) , and (4,20) to lie on the same straight line?

if so,
method I : find the equation of the line using the two known points, then sub in y=9

Method II : just set up a ratio ...
(x+2)/(9-2) = (4+2)/(20-2)
(x+2)/7 = 1/3
3x + 6 = 7
x = 1/3

how do you graph the function for p(x)=2x^2=12,500 where x is the number of items sold x(underscore)>3

To find the value of x when y is 9, we need to solve the equation using the given points (-2,2) and (4,20).

1. First, let's write the equation of the line passing through the two points using the slope-intercept form: y = mx + b, where m is the slope and b is the y-intercept.

2. Calculate the slope (m) using the formula: m = (y2 - y1) / (x2 - x1), where (x1, y1) = (-2, 2) and (x2, y2) = (4, 20). Substituting the values:
m = (20 - 2) / (4 - (-2))
= 18 / 6
= 3

3. Now we have the slope (m) as 3. Substitute the values of one of the points (let's use (-2,2)) and the slope (m) in the slope-intercept form to find the y-intercept (b).
y = mx + b (Using (-2,2))
2 = 3(-2) + b
2 = -6 + b
b = 2 + 6
b = 8

4. Now we have the equation of the line: y = 3x + 8. To find the value of x when y is 9, substitute y with 9 in the equation and solve for x.
9 = 3x + 8
3x = 9 - 8
3x = 1
x = 1 / 3

Therefore, when y is 9, the value of x is 1/3.