The equation P(x)= -2x^2+920x-84000 models the profit P, of selling x bikes. How many bikes would I have to sell to break even

Answer 1

-2x^2 + 920x - 84000 = 0

x^2 - 460x + 42000 = 0

[460 +or- sqrt ( (-460)^2 - 4 * 42000)] / 2 =

[460 +or- sqrt ( 211600 -168000]] / 2 =

[460 +or- sqrt (43600)] / 2 =

[460 +or- 208.80613017.....]/2 =

335 or 126

Answer 2

-920 / 2(-2) = ?