a) to get the profit to equal to 0
-x^2+6x+432=0
divide all by -1 to get rid of the negative in front
x^2-6x-432=0
factor
(x-24)(x+18)=0
x=21,-18
can’t sell -18 items so the answer is
24 ITEMS
b)maximize the profits meaning the maximum points aka. the VERTEX (where the graph is at its highest)
using x=-b/2a formula
you get x=3
to maximize the profit, they need to sell 3 items