statistical equasion

Well you'd follow the same steps shown here to graph the functions: https://www.khanacademy.org/math/cc-eighth-grade-math/cc-8th-linear-equations-functions/8th-solutions-to-two-var-linear-equations/v/plotting-x-y-relationships

Except that you'd probably want to start out around y = 2000 instead of 0, just a suggestion to save you some paper :) Though that means for y=8x, you won't be starting at x=0 because that'd be 0 (8*0), even x=100 would only be y=800 which is fairly far away from the y level you need to be at to see where the two graphs meet, aka intersect.

Some algebra, substituting 2000 for y would tell you'd need to start around x = 2000 / 8 (that won't be the exact intersection because the other function is y=2000 at x=0 but it's closer).

To find where they are equal you'd have to solve 6x+2000 = 8x
which is the same as 2000 = 8x - 6x. At the point where the two graphs intersect and they equal the same thing, then the profit - cost = 0 and therefore the company "breaks even" (neither making money nor losing money).

This isn't a KA video but it's the first one I found "using" a graph in a google search ("khan academy  breakeven") https://www.youtube.com/watch?v=2oQhIult0Cs