There goes my hopes for virtuoso
what are the zeros of the function y = x2 + 10x – 171, and why?
a) the zeros are x = –19 and x = 9 because in factored form, the function is y = (x – 19)(x + 9)
b) the zeros are x = –19 and x = 9 because in factored form, the function is y = (x + 19)(x – 9).
c) the zeros are x = 19 and x = –9 because in factored form, the function is y = (x – 19)(x + 9).
d) the zeros are x = 19 and x = –9 because in factored form, the function is y = (x + 19)(x – 9).

the answer   is 200

step-by-step explanation:

this is a problem about poisson probabilities.   i don't know if you've

already studied poisson distributions, or if you have a place to look

to read more about the subject.  

here's how you can see a poisson distribution coming.   when there are

a lot of events that may happen at any time (or any place), and when

you're counting how many of them happen at a particular time (or a

particular place), and each event is independent of the others, then

the result is a poisson distribution.   this is roughly true for the

chocolate chips; one chip being in a cookie has only a small effect on

the probability that another chip will be in the cookie.

once you know you have a poisson distribution, you know a lot.   there

is only one parameter to a poisson distribution, so if you know the

mean, you know everything.   the form of the distribution is

  probability of n chips = {[e^(-x)]*(x^n)} / (n! )

i can't see the picture : /