<span>12.3
Volume function: v(x) = ((18-x)(x-1)^2)/(4pi)
Since the perimeter of the piece of sheet metal is 36, the height of the tube created will be 36/2 - x = 18-x.
The volume of the tube will be the area of the cross section multiplied by the height. The area of the cross section will be pi r^2 and r will be (x-1)/(2pi). So the volume of the tube is
v(x) = (18-x)pi((x-1)/(2pi))^2
v(x) = (18-x)pi((x-1)^2/(4pi^2))
v(x) = ((18-x)(x-1)^2)/(4pi)
The maximum volume will happen when the value of the first derivative is zero. So calculate the first derivative:
v'(x) = (x-1)(3x - 37) / (4pi)
Convert to quadratic equation.
(3x^2 - 40x + 37)/(4pi) = 0
3/(4pi)x^2 - (10/pi)x + 37/(4pi) = 0
Now calculate the roots using the quadratic formula with a = 3/(4pi), b = -10/pi, and c = 37/(4pi)
The roots occur at x = 1 and x = 12 1/3. There are the points where the slope of the volume equation is zero. The root of 1 happens just as the volume of the tube is 0. So the root of 12 1/3 is the value you want where the volume of the tube is maximized. So the answer to the nearest tenth is 12.3</span>
Below represents the proof that the quadrilateral QRST is a parallelogram
<h3>How to prove that QRST is a parallelogram?</h3>
The coordinates are given as:
Q = (-1,-1)
R = (2,9)
S = (-4,5)
T = (-7,-5)
Calculate the length of each side using:

So, we have:




The above computations show that opposite sides are equal.
Next, we determine the slope of each side using:

So, we have:




The above computations show that opposite sides are parallel, because they have equal slope
Hence, the quadrilateral QRST is a parallelogram
Read more about parallelograms at:
brainly.com/question/3050890
#SPJ1
Answer:
hmmmmmmm
Step-by-step explanation:
nah I am good thx for the free points
1. Observe question
2. Employ Point-Slope formula
(y2 - y1)/(x2 - x1 )=
(-10-9)/(-6-9) =
-19/-15=
19/15
Slope: 19/15
9514 1404 393
Answer:
A) 504
B) 8
Step-by-step explanation:
The statement of proportionality can be written as the equation ...
m = kr²
Then we can find k from ...
k = m/r² = 14/2² = 7/2
That is, ...
m = (7/2)r²
__
Using this relation, we can find m for r=12:
m = (7/2)·12² = 7·72
m = 504 . . . for r = 12
__
And, we can use the same equation to solve for r when m=224.
224 = 7/2·r²
r² = 64
r = √64
r = 8 . . . for m = 224