Please help fast, thanks.

Please Help Fast, Thanks.

Answers

Answer 1

Answer:

b > 100

Step-by-step explanation:


Related Questions

The portion of the parabola y²=4ax above the x-axis, where is form 0 to h is revolved about the x-axis. Show that the surface area generated is
A=8/3π√a[(h+a)³/²-a³/2]
Use the result to find the value of h if the parabola y²=36x when revolved about the x-axis is to have surface area 1000.​

Answers

Answer:

See below for Part A.

Part B)

[tex]\displaystyle h=\Big(\frac{125}{\pi}+27\Big)^\frac{2}{3}-9\approx7.4614[/tex]

Step-by-step explanation:

Part A)

The parabola given by the equation:

[tex]y^2=4ax[/tex]

From 0 to h is revolved about the x-axis.

We can take the principal square root of both sides to acquire our function:

[tex]y=f(x)=\sqrt{4ax}[/tex]

Please refer to the attachment below for the sketch.

The area of a surface of revolution is given by:

[tex]\displaystyle S=2\pi\int_{a}^{b}r(x)\sqrt{1+\big[f^\prime(x)]^2} \,dx[/tex]

Where r(x) is the distance between f and the axis of revolution.

From the sketch, we can see that the distance between f and the AoR is simply our equation y. Hence:

[tex]r(x)=y(x)=\sqrt{4ax}[/tex]

Now, we will need to find f’(x). We know that:

[tex]f(x)=\sqrt{4ax}[/tex]

Then by the chain rule, f’(x) is:

[tex]\displaystyle f^\prime(x)=\frac{1}{2\sqrt{4ax}}\cdot4a=\frac{2a}{\sqrt{4ax}}[/tex]

For our limits of integration, we are going from 0 to h.

Hence, our integral becomes:

[tex]\displaystyle S=2\pi\int_{0}^{h}(\sqrt{4ax})\sqrt{1+\Big(\frac{2a}{\sqrt{4ax}}\Big)^2}\, dx[/tex]

Simplify:

[tex]\displaystyle S=2\pi\int_{0}^{h}\sqrt{4ax}\Big(\sqrt{1+\frac{4a^2}{4ax}}\Big)\,dx[/tex]

Combine roots;

[tex]\displaystyle S=2\pi\int_{0}^{h}\sqrt{4ax\Big(1+\frac{4a^2}{4ax}\Big)}\,dx[/tex]

Simplify:

[tex]\displaystyle S=2\pi\int_{0}^{h}\sqrt{4ax+4a^2}\, dx[/tex]

Integrate. We can consider using u-substitution. We will let:

[tex]u=4ax+4a^2\text{ then } du=4a\, dx[/tex]

We also need to change our limits of integration. So:

[tex]u=4a(0)+4a^2=4a^2\text{ and } \\ u=4a(h)+4a^2=4ah+4a^2[/tex]

Hence, our new integral is:

[tex]\displaystyle S=2\pi\int_{4a^2}^{4ah+4a^2}\sqrt{u}\, \Big(\frac{1}{4a}\Big)du[/tex]

Simplify and integrate:

[tex]\displaystyle S=\frac{\pi}{2a}\Big[\,\frac{2}{3}u^{\frac{3}{2}}\Big|^{4ah+4a^2}_{4a^2}\Big][/tex]

Simplify:

[tex]\displaystyle S=\frac{\pi}{3a}\Big[\, u^\frac{3}{2}\Big|^{4ah+4a^2}_{4a^2}\Big][/tex]

FTC:

[tex]\displaystyle S=\frac{\pi}{3a}\Big[(4ah+4a^2)^\frac{3}{2}-(4a^2)^\frac{3}{2}\Big][/tex]

Simplify each term. For the first term, we have:

[tex]\displaystyle (4ah+4a^2)^\frac{3}{2}[/tex]

We can factor out the 4a:

[tex]\displaystyle =(4a)^\frac{3}{2}(h+a)^\frac{3}{2}[/tex]

Simplify:

[tex]\displaystyle =8a^\frac{3}{2}(h+a)^\frac{3}{2}[/tex]

For the second term, we have:

[tex]\displaystyle (4a^2)^\frac{3}{2}[/tex]

Simplify:

[tex]\displaystyle =(2a)^3[/tex]

Hence:

[tex]\displaystyle =8a^3[/tex]

Thus, our equation becomes:

[tex]\displaystyle S=\frac{\pi}{3a}\Big[8a^\frac{3}{2}(h+a)^\frac{3}{2}-8a^3\Big][/tex]

We can factor out an 8a^(3/2). Hence:

[tex]\displaystyle S=\frac{\pi}{3a}(8a^\frac{3}{2})\Big[(h+a)^\frac{3}{2}-a^\frac{3}{2}\Big][/tex]

Simplify:

[tex]\displaystyle S=\frac{8\pi}{3}\sqrt{a}\Big[(h+a)^\frac{3}{2}-a^\frac{3}{2}\Big][/tex]

Hence, we have verified the surface area generated by the function.

Part B)

We have:

[tex]y^2=36x[/tex]

We can rewrite this as:

[tex]y^2=4(9)x[/tex]

Hence, a=9.

The surface area is 1000. So, S=1000.

Therefore, with our equation:

[tex]\displaystyle S=\frac{8\pi}{3}\sqrt{a}\Big[(h+a)^\frac{3}{2}-a^\frac{3}{2}\Big][/tex]

We can write:

[tex]\displaystyle 1000=\frac{8\pi}{3}\sqrt{9}\Big[(h+9)^\frac{3}{2}-9^\frac{3}{2}\Big][/tex]

Solve for h. Simplify:

[tex]\displaystyle 1000=8\pi\Big[(h+9)^\frac{3}{2}-27\Big][/tex]

Divide both sides by 8π:

[tex]\displaystyle \frac{125}{\pi}=(h+9)^\frac{3}{2}-27[/tex]

Isolate term:

[tex]\displaystyle \frac{125}{\pi}+27=(h+9)^\frac{3}{2}[/tex]

Raise both sides to 2/3:

[tex]\displaystyle \Big(\frac{125}{\pi}+27\Big)^\frac{2}{3}=h+9[/tex]

Hence, the value of h is:

[tex]\displaystyle h=\Big(\frac{125}{\pi}+27\Big)^\frac{2}{3}-9\approx7.4614[/tex]

You seem to have left out that 0 ≤ x ≤ h.

From y² = 4ax, we get that the top half of the parabola (the part that lies in the first quadrant above the x-axis) is given by y = √(4ax) = 2√(ax). Then the area of the surface obtained by revolving this curve between x = 0 and x = h about the x-axis is

[tex]2\pi\displaystyle\int_0^h y(x) \sqrt{1+\left(\frac{\mathrm dy(x)}{\mathrm dx}\right)^2}\,\mathrm dx[/tex]

We have

y(x) = 2√(ax)   →   y'(x) = 2 • a/(2√(ax)) = √(a/x)

so the integral is

[tex]4\sqrt a\pi\displaystyle\int_0^h \sqrt x \sqrt{1+\frac ax}\,\mathrm dx[/tex]

[tex]=\displaystyle4\sqrt a\pi\int_0^h (x+a)^{\frac12}\,\mathrm dx[/tex]

[tex]=4\sqrt a\pi\left[\dfrac23(x+a)^{\frac32}\right]_0^h[/tex]

[tex]=\dfrac{8\pi\sqrt a}3\left((h+a)^{\frac32}-a^{\frac32}\right)[/tex]

Now, if y² = 36x, then a = 9. So if the area is 1000, solve for h :

[tex]1000=8\pi\left((h+9)^{\frac32}-27\right)[/tex]

[tex]\dfrac{125}\pi=(h+9)^{\frac32}-27[/tex]

[tex]\dfrac{125+27\pi}\pi=(h+9)^{\frac32}[/tex]

[tex]\left(\dfrac{125+27\pi}\pi\right)^{\frac23}=h+9[/tex]

[tex]\boxed{h=\left(\dfrac{125+27\pi}\pi\right)^{\frac23}-9}[/tex]

solve the equations 7(x+4)=21
iready​

Answers

Step-by-step explanation:

[tex]\bullet\hookrightarrow\sf 7 (x+4)=21 [/tex]

[tex]\bullet\Rrightarrow\sf 7x+28=21 [/tex]

[tex]\bullet\rightarrowtail\sf 7x=21-28 [/tex]

[tex]\bullet\twoheadrightarrow\sf 7x=-7 [/tex]

[tex]\bullet\looparrowright\sf x=\dfrac{-7}{7}[/tex]

[tex]\bullet\rightharpoonup\sf x=-1 [/tex]

The mass of a textbook is 1.25 kg about how many pounds is this

Answers

Answer:

2.755778

Step-by-step explanation:

Just search how much pounds is 1.25 kg?

This package of sliced cheese costs $2.97, How much would a package with 18 slices cost at the same price per slice

Answers

Answer:

Cant you just type that in the calculator 18 times lol

Step-by-step explanation:

use a calculator

the perimeter of the ussoscales triangle is 48cm calculate the length of BC​

Answers

Answer:

where is the pic............

we need the pic 2 answer your question sir

Use the Distributive Property to expand the expression -3(6.3x + 1.5y)

Answers

Answer:

(-3*6.3x)+(-3*1.5y)

(-18.9x)+(-4.5y)

Use the graph below to find f(-2) =

Answers

f(-2) is when x = -2
On the graph it’s (-2, 2)
Solution: f(-2) = 2

24 is what percent of 12?

need help? anyone know this?

Answers

Answer:

200

Step-by-step explanation:

You need to purchase supplies for an employee appreciation picnic. Your boss gives you the shopping list below and asks that you get the best deal by buying from one grocer, either Quality Groceries or Fresh Market. You call both grocers, and they provide the price information that you put into the table. Which grocer will provide all these picnic supplies for the lowest cost, and what is that cost without sales tax?

Hamburger Patties 50
Hot Dogs 2 dozen
Hamburger Buns 50
Hot Dog Buns 2 dozen
Potato Salad 2 gallons
Ice Cream 5 gallons
Product Quality Groceries Unit Quality Groceries Price per Unit Fresh Market Unit Fresh Market Price per Unit
Hamburger Patties Package of 10 $15.50 Package of 8 $12.40
Hot Dogs Package of 12 $6.23 Package of 10 $4.99
Hamburger Buns Package of 8 $3.79 Package of 8 $3.55
Hot Dog Buns Package of 12 $2.75 Package of 8 $2.55
Potato Salad Gallon $4.33 Gallon $5.55
Ice Cream Gallon $7.55 Gallon $6.99

Answers

Is there picture to go along with this?

Answer:

this doesnt make sense is there any type of picture or more explanation on the question? i'll still help :)

Step-by-step explanation:

A rhombus is not a
a. polygon. c. trapezoid.
b. parallelogram. d. quadrilateral.

Answers

Answer:

polygon

Step-by-step explanation:

A polygon is any 2-dimensional shape formed with straight lines. Triangles, quadrilaterals, pentagons, and hexagons are all examples of polygons. A rhombus has 4 sides.

Hope this helps:) Have a great day!

The temperature went from 90° to 60°. What is the percent decrease? Round to the nearest percent.
1)30%
2)33%
3) 60%
4)66%

Answers

It is 3 trust me I think it is

What is the slope of a line that passes through the following points (4, 6) and (2, 0)?

Answers

Answer:

3

Step-by-step explanation:

Step-by-step explanation:

formula to fine slope

m=tan()=y2-y1/x2-x1

3. To make purple frosting, you start with white frosting.
Then you add 2 drops of red food coloring and 3 drops of
blue food coloring. If 4 red drops come out with the first
squeeze, how many blue drops should you add?

Answers

Answer:  6 drops of blue

==================================================

Explanation:

We basically mix red and blue to get purple. The ratio needed is 2 parts red, and 3 parts blue. We can shorten this by writing 2:3

Note how we can double both parts of the ratio to get 4:6, showing that 4 drops of red correspond to 6 drops of blue, which is the answer we want.

------------------

Another approach:

x = some positive real number

(2 parts red)/(3 parts blue) = (4 parts red)/(x parts blue)

2/3 = 4/x

2x = 3*4 .... cross multiply

2x = 12

x = 12/2 .... divide both sides by 2

x = 6

So 6 drops of blue go with 4 drops of red.

Drag the missing word into place
swhen they enter the balls throw
Or you run real quick to get home
Solar
ENGTE
Kinetic

Answers

Answer:

kinetic energy

Step-by-step explanation:

When a person runs, their body must convert potential energy into kinetic energy.

Buster needs to find x and y in the following system.
Equation A: - 8x + 14y = 10
Equation B: 4x + 3y = 25
Buster decided to use elimination to solve this system. Do you agree or disagree? Why

Answers

Answer:

U GO TO DHS

Step-by-step explanation:

What’s the answer to this radical functions equation ASAP

Answers

Step-by-step explanation:

√z is defined only when z >= 0

Therefore √x - 1 is defined only when (x - 1) >= 0, x >= 1.

The only graph that shows the domain x >= 1 is graph Y.

Carmen quiere invertir 700 dólares, de tal forma que en
90 días le produzca 63 dólares de interés simple.
¿Que tasa de interés debe elegir?

Answers

La fórmula de interés simple, nos permite calcular I, que es el interés ganado o pagado de un préstamo. Según esta fórmula, la cantidad de interés está dada por I = C·i·t, donde C es el capital, i es la tasa de interés anual en forma decimal, y t es el período de tiempo expresado en años Tenemos que:

C = 700 dólares

i  = ???

t = 90/360 = 0.25 (Expresado en años)

I = C*i * t

i = I / C*t

i = 63/ (0.25*700)

i = 0.36

R/ Debe elegir una tasa de interés de 36% anual.

The interest on the amount invested for 90days given $63 as interest is 36.5%

Simple interest is the amount of money added to money invested. It is calculated as:

[tex]SI = \frac{PRT}{100}[/tex]

P is the amount invested (principal) = $700

R is the rate

T is the time (in years) = 90/365

SI is the interest = $63

Substitute the given values into the formula

[tex]63=\frac{700 \times R \times 90}{365 \times 100}\\63=\frac{63000R}{36500}\\63= 1.72602R\\R=36.5\%[/tex]

This shows that the interest on the amount invested for 90days given $63 as interest is 36.5%

Learn more here: https://brainly.com/question/21640787

Given that the triangles shown below are similar, what is the value of x?
D
32
40
16
20
H
48
M
P
X
L
A. 20
O
B. 10.7
O
C. 96
O D. 24

Answers

Answer:

the answer is D. 24

Step-by-step explanation:

the smaller triangle is half the size of the bigger triangle so just divide 48 by 2

Answer: D

Why?

Question tells you that both triangles are similar, but the obvious difference is that one is smaller than the other.

As u can see HA = PD
32 = 16
The difference is 2

By dividing the value of HM (which is 48) u can get the answer 24.

Therefore the answer is D

Kesha it’s plain to rent a van for a trip to Mt.rainier two of her friends each went to the same type of van from the same car rental company last week

Answers

Answer:

a

Step-by-step explanation:

Bags of pretzels are sampled to ensure proper weight. The overall average for the samples is 9 ounces. Each sample contains 25 bags. The standard deviation is estimated to be 3 ounces. The upper control chart limit (for 99.7% confidence) for the average would be ________ ounces.

Answers

Answer:

The value is [tex]UCL = 10.8[/tex]  

Step-by-step explanation:

From the question we are told that

    The sample mean is  [tex]\= x = 9 \ ounce[/tex]

    The sample size is  n =  25

    The standard deviation is  [tex]\sigma = 3 \ ounce[/tex]

Given that the sample size is not large enough i.e  n<  30  we will make use of the student t distribution table  

From the question we are told the confidence level is  99.7% , hence the level of significance is    

      [tex]\alpha = (100 -99.7 ) \%[/tex]

=>   [tex]\alpha = 0.003[/tex]

Generally the degree of freedom is  [tex]df = n- 1[/tex]

=>  [tex]df = 25 - 1[/tex]

=>  [tex]df = 24[/tex]  

Generally from the student t distribution table the critical value  of  [tex]\frac{\alpha }{2}[/tex] at a degree of freedom of [tex]df = 24[/tex]   is  

   [tex]t_{\frac{\alpha }{2} , 24 } = 3.0 [/tex]

Generally the margin of error is mathematically represented as  

      [tex]E = t_{\frac{\alpha }{2} , 24} *  \frac{\sigma }{\sqrt{n} }[/tex]

=>     [tex]E = 3.0 *  \frac{3 }{\sqrt{25} }[/tex]

=>     [tex]E =1.8 [/tex]

Gnerally the  upper control chart limit  for 99.7% confidence is mathematically represented as

         [tex]UCL = \= x + E[/tex]

=>      [tex]UCL = 9 + 1.8[/tex]  

=>      [tex]UCL = 10.8[/tex]  

     

Expand and simplify
3(x + 5) + 2(x + 4)

Answers

3(x+5) + 2(x+4)
3x+15+2x+8
The answer is 5x+23

Answer:

5x + 23

Step-by-step explanation:

3 ( x+5) + 2 ( x+4 )

3x+15+2x+8

3x+2x+8+15

5x+23

|7-8| • 4 + 3 (-1) ???????

Answers

Answer:

1

Step-by-step explanation:

|7-8| • 4 + 3 (-1) =

= |-1| • 4 + (-3)

= 1 • 4 - 3

= 4 - 3

= 1

How can this expression be written another way?

Apply the distributive property and the greatest common factor to write an equivalent expression.

Enter your answer by filling in the boxes.

105 + 35m = __ (__)

Answers

Answer:

(105 x 30) + (105 x 5) + m

Step-by-step explanation:

Answer:

(105 x 30) + (105 x 5) + m

Step-by-step explanation:

Hope this helped have an amazing day!

What is the slope of the line represented by the equation y=X3?
40 Points I need help doing a test !!

Answers

Answer:

B

Step-by-step explanation:

trust

Answer:c) 4/5

Step-by-step explanation:

y= mx+c, here, m is the slope.

In this case, m= 4/5, c= -3

x2 + kx + (k + 3) is tangent to x-axis. Find the value
of k.​

Answers

Step-by-step explanation:

Since x² + kx + (k + 3) is tangent to the x-axis, the quadratic function has a repeated root.

The discriminant is zero, so b² - 4ac = 0.

=> k² - 4(1)(k + 3) = 0

=> k² - 4k - 12 = 0

=> (k - 6)(k + 2) = 0

Hence k = 6 or k = -2.

The value of k is -2 and 6.

What is an equation?

An equation is a mathematical statement that is made up of two expressions connected by an equal sign.

Example:

2x + 4 = 9 is an equation.

We have,

x² + kx + (k + 3) is tangent to the x-axis.

This means,

The equation has roots.

Now,

The determinant of the equation is equal to zero.

D = b² - 4ac

x² + kx + (k + 3) is in the form of ax² + bx + c.

a = 1

b = k

c = k + 3

Now,

D = 0

k² - 4(k + 3) = 0

k² - 4k - 12 = 0

k² - (6 - 2)k - 12 = 0

k² - 6k + 2k - 12 = 0

k(k - 6) + 2(k - 6) = 0

(k + 2) (k - 6) = 0

k + 2 = 0

k = -2

k - 6 = 0

k = 6

Thus,

k = -2 and 6.

Learn more about equations here:

https://brainly.com/question/17194269

#SPJ2


How much simple interest does $5,000 earn in 4 years at an interest rate of 5%. Round to
the nearest cent.

Answers

Answer:

1000

Step-by-step explanation:

What is the zero of 4x - 3y = -24?

Answers

The answer is 4x-3y+24=0

PLease im almost out of time

Answers

There is no question so currently, I am unable to help you.

0 = 4 + n/5 two step equations​

Answers

Answer: n= -20?

Step-by-step:

Simplify both sides of the equation

1/5n+4=0

Then subtract 4 from both sides

1/5n + 4 - 4 = 0 - 4

1/5n= -4

Then multiply both sides by 5

5*(1/5n)=5*(-4)

Answer:

0=n

Step-by-step explanation:

1. 0=4+n/5

add 4 and n

2. 0=4n/5

×5. ×5

3. 0=4n

-- --

4 4

4. 0=n

Look at the picture for a more detailed steps

Ron measured his garden to be 12‘ x 8 1/3‘. He plant vegetables in 3/4 of his garden. What is the area of his vegetable garden?

Answers

Answer:

4/4

Step-by-step explanation:

Hope this helped have an amazing day!

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