Answer:
![h = \sqrt[3]{\frac{49V}{4}}](https://tex.z-dn.net/?f=h%20%3D%20%5Csqrt%5B3%5D%7B%5Cfrac%7B49V%7D%7B4%7D%7D)
Step-by-step explanation:
Represent the volume of the box with V and the dimensions with l, b and h.
The volume (V) is:

Make h the subject of the formula

The surface area (S) of the aquarium is:

Where lb represents the area of the base (i.e. slate):
The cost (C) of the surface area is:



Substitute
for h in the above equation



Differentiate with respect to l and with respect to b


To solve for b and l, we equate both equations and set l to b (to minimize the cost)


By comparison:

becomes

Cross Multiply

Solve for l

![l = \sqrt[3]{\frac{2V}{7}}](https://tex.z-dn.net/?f=l%20%3D%20%5Csqrt%5B3%5D%7B%5Cfrac%7B2V%7D%7B7%7D%7D)
Recall that: 
![b = \sqrt[3]{\frac{2V}{7}}](https://tex.z-dn.net/?f=b%20%3D%20%5Csqrt%5B3%5D%7B%5Cfrac%7B2V%7D%7B7%7D%7D)
Also recall that:

![h = \frac{V}{\sqrt[3]{\frac{2V}{7}}*\sqrt[3]{\frac{2V}{7}}}](https://tex.z-dn.net/?f=h%20%3D%20%5Cfrac%7BV%7D%7B%5Csqrt%5B3%5D%7B%5Cfrac%7B2V%7D%7B7%7D%7D%2A%5Csqrt%5B3%5D%7B%5Cfrac%7B2V%7D%7B7%7D%7D%7D)
![h = \frac{V}{\sqrt[3]{\frac{4V^2}{49}}}](https://tex.z-dn.net/?f=h%20%3D%20%5Cfrac%7BV%7D%7B%5Csqrt%5B3%5D%7B%5Cfrac%7B4V%5E2%7D%7B49%7D%7D%7D)
Apply law of indices
![h = \sqrt[3]{\frac{49V^3}{4V^2}}](https://tex.z-dn.net/?f=h%20%3D%20%5Csqrt%5B3%5D%7B%5Cfrac%7B49V%5E3%7D%7B4V%5E2%7D%7D)
![h = \sqrt[3]{\frac{49V}{4}}](https://tex.z-dn.net/?f=h%20%3D%20%5Csqrt%5B3%5D%7B%5Cfrac%7B49V%7D%7B4%7D%7D)
The dimension that minimizes the cost of material of the aquarium is:
![h = \sqrt[3]{\frac{49V}{4}}](https://tex.z-dn.net/?f=h%20%3D%20%5Csqrt%5B3%5D%7B%5Cfrac%7B49V%7D%7B4%7D%7D)
Answer:

Step-by-step explanation:
The exponential function that decrease by 15% every time x increases by 1 is given by:

We simplify the parenthesis to get:

Therefore the decrease by 15% every time x increases by 1 is

The second choice is correct.
Answer:

Step-by-step explanation:
<em>See Attachment for Complete Question</em>
Given
--- For the forest
-- --- For the forest
Required
Determine the area of the habitat
Since the distance between the animal's habitat is x mi on both sides;
The length and width of the habitat is:




The area is then calculated as follows;


Expand

Open Brackets


Reorder

Hence; the required polynomial for the habitat area is:

Answer: 0.0099
Step-by-step explanation:
Given
jacinta buys 4 pounds of turkey and 2 pounds of ham & pays a total of $30, turkey costs $1.50 less per pound than the ham.
find out the combined cost of 1 pound of turkey and 1 pound of ham
To proof
As given in the question
jacinta buys 4 pounds of turkey and 2 pounds of ham
total pay by jacinta = $30
let us assume that the price of the ham = x
as given in the question
turkey costs $1.50 less per pound than the ham
turkey costs becomes = x - 1.50
then the equation becomes
30 = 4 (x - 1.50) + 2x
30 = 4x + 2x - 6
36 = 6x
x = 6
thus
ham cost per pound = $6
turkey cost per pound = 6 - 1.50
= $ 4.5
Now find out
cost of 1 pound of turkey + 1 pound of ham = $ 6 + $ 4.5
= $ 10.5
Hence proved