The profit function P(x) will be zero when either of its factors is zero. The left factor (x-3) is zero when x=3. The right factor (x-11) is zero when x=11.
Prices of $3 or $11 will result in $0 annual profit.
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<em>Additional comment</em>
A price halfway between these values, at (3+11)/2 = 7, will produce maximum profit, $32 million.
I think that it would be 8 inches because to find the area of a triangle is base times height divided by two. So I just doubled the area and divided by 6.
Since they already charged her $2.00 leave that alone. They charge her .50 per night, x represents the number of nights she rented the movie. thus the answer is c(x) = 2.00 + 0.50x.