SOLUTION: The number of people infected after t days is P=200+5t-t^2. Find the number of days until the number of people infected is 176. Help! What are the steps to solve this equation?

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Question 256876: The number of people infected after t days is P=200+5t-t^2.
Find the number of days until the number of people infected is 176.
Help! What are the steps to solve this equation?
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
We start with the equation:
P=200%2B5t-t%5E2
P = 176, so we get
176+=+200+%2B+5t+-+t%5E2
So, we get
t%5E2+-+5t+-24+=+0
factoring, we get
%28t-8%29%28t%2B3%29=0
solving for t, we get
t = 8; t = -3.
Since time is not negative, we get
t = 8 days