If x represents the width of the poster (including borders), the area of the finished poster can be written as
.. a = x*(390/(x -10) +8)
.. = 8x +390 +3900/(x -10)
Then the derivative with respect to x is
.. da/dx = 8 -3900/(x -10)^2
This is zero at the minimum area, where
.. x = √(3900/8) +10 ≈ 32.08 . . . . cm
The height is then
.. 390/(x -10) +8 = 8 +2√78 ≈ 25.66 . . . . cm
The poster with the smallest area is 32.08 cm wide by 25.66 cm tall.
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In these "border" problems, the smallest area will have the same overall dimension ratio that the borders have. Here, the poster is 10/8 = 1.25 times as wide as it is high.
The cost of the 9th item is $3.94
Since the mean cost for the 9 items in his bag was $2.71. Then, the total cost will be: = 9 × $2.71 = $24.39
In order to get the price of the 9th item, we have to calculate the price of all the 8 items given which will be:
$2.01 + $2.20 + $2.68 + $3.59 + $3.12 + $1.64, + $1.75 + $3.46 = $20.45
Therefore, the cost of the 9th item will be:
= $24.39 - $20.45
= $3.94
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Answer:
A cube
Step-by-step explanation:
If you fold it, you'll see
Answer:
4,845
Step-by-step explanation:
Hope this helps:)
Answer: y=4x-23
Step-by-step explanation:
First multiply the 4 on the right side to make it y+3=4x-20. Then subtract 3 on both sides to get y=4x-23
