Answer:
The expression 
represents the radius of the soap dispenser.
The expression 
represents the height of the soap dispenser.
Step-by-step explanation:
The question says that the soap dispenser is in the form of a cylinder.
Now, we find the volume of the cylinder by using the given formula:
, where V represents the volume, 'r' represents the radius, and 'h' represents the height of the cylinder.
Now, the volume is the product of radius squared and the height, if they both are functions of 
, then the function to represent the volume must have cubic exponents.
Since, the radius is squared in the formula and it is a function of that implies that the function of radius must have square as the exponent of , therefore, the expression will represent the radius of the soap dispenser and the expression 
represents the height of the soap dispenser.
Answer:
625 metres
Step-by-step explanation:
Given the area function expressed as a(w)=-(w-25)^2+625.
The maximum area occurs at when da/dw = 0
da/dw = -2(w-25)
0 = -2(w-25)
-2(w-25) = 0
w - 25 = 0
w = 25
Substitute w = 25 into the modeled equation;
Recall a(w)=-(w-25)^2+625.
a(25)=-(25-25)^2+625
a(25) = 0+625
a(25) = 625
Hence the maximum area possible is 625 metres
This is geometry through and through. Plus a little trig thrown in for fun. If you inscribe an equilateral triangle inside a circle and the triangle has side lengths of 12, you have part of what you need to use Pythagorean's Theorem to find the hypotenuse of the triangle which is also the radius of the circle. First, use the formula 360/3 to find that the central angle measure of each angle INSIDE a triangle is 120. So you have 3 triangles within the large one, each with a top angle of 120 and a base of 12. If you extract that one triangle and then split it in half, you have a right triangle with a base of 6. This is a 30-60-90 triangle and this is important so you can check your work. Now use the apothem formula for a right triangle as it relates to a side in an equilateral triangle, which is a = sqrt3/6 * s. Our values are a = sqrt3/6(12) which simplifies to 2sqrt3. That's our apothem. If you're familiar with a 30-60-0 triangle, you could check this to see it's correct. Now you have the base leg of 6 and the height of 2sqrt3, now use Pythagorean's Theorem to find the hypotenuse, which is also the radius of the circle. This was really a difficult one to explain.
