Answer:
Step-by-step explanation:
(2):
First let's organise the data:
33 miles ... x mph ... 4h - downstream
33 miles ... y mph ... 7h - up the stream
x = 33/4 = 8.25 mph
y = 33/7 = 4.71 mph
(3)
P(x) = [tex]x^2 - 2x - 3[/tex]
To find the amount of key rings sold when the profit is 5000$ we have to equate P(x) with 5, because in the problem the profit of the key rings is displayed in terms of thousands.
[tex]x^2 - 2x - 3 = 5\\x^2 - 2x - 8 = 0\\x_1 = 4, x_2 = -2[/tex]
Since the number of keyrings sold has to be positive the only answer is 4 thousand key rings.
