Answer:
7536 
Step-by-step explanation:
Given that:
Rate of decreasing of radius = 12 km/sec
Height of cylinder is fixed at = 2.5 km
Radius of cylinder = 40 km
To find:
The rate of change of Volume of the cylinder?
Solution:
First of all, let us have a look at the formula for volume of a cylinder.

Where
is the radius and
is the height of cylinder.
As per question statement:
= 40 km (variable)
= 2.5 (constant)

As
are constant:

Louise wants to factorize completely the given polynomial 
Grouping first, second terms together and third, fourth terms together
= 
Taking
common from first and second terms of the given expression and taking 5 common from the third and fourth terms.
=
Taking (x+3) common from the given expression,
=
is the completely factored form.
3n² - 8n + 4
3n² - 6n - 2n + 4
(3n - 2)(n - 2)
Answer:
x = 8
y = 11
Step-by-step explanation:
Total small box weight = 50x [x being the number of small boxes]
Total large box weight = 80y [y being the number of large boxes]
Total boxes = x+y = 19
Total weight = 1280
<em>Determine x and y.</em>
<u>You know 2 equations. One for weight and another for number of boxes each.</u>
<u>Rewrite second equation:</u>
x+y=19
y=19-x
<u>You have to plug in one into another.</u>
1280 = 50x + 80(19-x)
<u>Solve for x</u>
1280 = 50x + 1520 - 80x
-240 = -30x
x = 8
<u>Solve for y by plugging in x into one of the equations:</u>
8+y = 19
y = 11
Y α xz
y = kxz y = 72, when x = 6, and z = 4
72 = k*6*4
72 = k*24
24k = 72
k = 72/24
k = 3.
<span>y = kxz
</span>
<span>y = 3xz </span>
Finding y, when x = 3, z = 5.
y = 3xz
y = 3*3*5
y = 45