Which of the following expressions is equal to -3x^2-12?

Answer:

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

(-18.9x)+(-4.5y)

Answer:

1000

Step-by-step explanation:

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]

Answer:

the answer is D

Step-by-step explanation:

A. √123 = 11.09

11.09-11 = 0.09

B. √115 = 10.72

11-10.72 = 0.28

C. √118 = 10.86

11-10.86 = 0.14

D. √120 = 10.95

11-10.95 = 0.05 ( the smallest difference )

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:

Answer:

Step-by-step explanation:

Answer:

a. Angel has a greater flat fee

b. Difference = $130

Step-by-step explanation:

Given

Rose:

[tex]Flat\ Fee = \$50[/tex]

[tex]Rate = \$12[/tex]

Angel

Guests --- Charges

10 -------- $180

15 -------- $255

25 -------- $405

30 -------- $480

Solving (a): Who charges the greater flat fee?

We have that the flat fee of Rose is:

[tex]Flat\ Fee = \$50[/tex]

For Angel, we need to determine the equation of the given table

Start by calculating the slope (m) of the table

[tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex]

Where x and y represent any two corresponding values of the guests and the charges.

[tex](x_1,y_1) = (10, 180)[/tex]

[tex](x_2,y_2) = (30, 480)[/tex]

So: [tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex] becomes

[tex]m = \frac{480 - 180}{30 - 10}[/tex]

[tex]m = \frac{300}{20}[/tex]

[tex]m = 15[/tex]

Next, we calculate the equation using:

[tex]y - y_1 = m(x - x_1)[/tex]

Where

[tex]m = 15[/tex]

[tex](x_1,y_1) = (10, 180)[/tex]

[tex]y - 180 = 15(x - 10)[/tex]

[tex]y - 180 = 15x - 150[/tex]

Add 180 to both sides

[tex]y - 180 + 180 = 15x - 150 + 180[/tex]

[tex]y= 15x + 30[/tex]

From the equation above:

The slope = 15 --- This represents the hourly rate

and

y intercept = 30 --- This represents the flat fee

This is better represented as:

Angel

[tex]Flat\ Fee = \$30[/tex]

[tex]Rate = \$15[/tex]

and

Rose:

[tex]Flat\ Fee = \$50[/tex]

[tex]Rate = \$12[/tex]

By comparison, Angel has a greater flat fee

Solving (b): Difference between total charges of 50 guests for both caterers.

For angel, the equation is:

[tex]y= 15x + 30[/tex]

and x = 50.

So:

[tex]y = 15 * 50 + 30[/tex]

[tex]y = 750 + 30[/tex]

[tex]y = 780[/tex]

For Rose,

First, we need to determine the equation.

[tex]Flat\ Fee = \$50[/tex]

[tex]Rate = \$12[/tex]

The equation is:

[tex]y = Flat\ Fee + Rate * x[/tex]

[tex]y = 50 + 12 * x[/tex]

So, the total charges for 50 guests is:

[tex]y = 50 + 12 * 50[/tex]

[tex]y = 50 + 600[/tex]

[tex]y = 650[/tex]

The difference is then calculates as:

[tex]Difference = 780 - 650[/tex]

[tex]Difference = \$130[/tex]

Answer:

42

Step-by-step explanation:

uih

Answer:

2.755778

Step-by-step explanation:

Just search how much pounds is 1.25 kg?

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!

Answer:

9.3

Step-by-step explanation:

6.2 x 15/10= 9.3

Answer:

Scientific notation is 1.6 x 10^16 and in regular format is:

160000000000000000

Answer: C

Step-by-step explanation:

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]

Answer:

y=x-2

Hope this helps.

Answer:

kinetic energy

Step-by-step explanation:

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

Answer:

U GO TO DHS

Step-by-step explanation:

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]  

Answer:

8/15= 0.533

Step-by-step explanation:

8 divided by 15 isn't possible so according to the rules of division we introduce a (0.) then we add a (0) to the back of (8) to make it (80) which is bigger than (15) so we now have (80/15) which is (5) remaining (5) then we add the back of the (0.) it then becomes (0.5) we then step down the remaining (5) and also add a (0) at the back to make it (50) which is also bigger than (15) (50/15) which gives us (3) and a remaining (5) add (3) to the back of (0.5) to become (0.53) also still step down the remaining (5) add a zero to it to become (50) still divide by (15) gives (3) and remains (5) and it gives the same answer so it is a reoccurring decimal.

Thank you hope I was of help!!

Answer:

25

Step-by-step explanation:

a2+b2=c2

3^2+4^2=c^2

9+16=25

25^2=625

Sqrt of 625 = 25

Answer:

x = 5

Step-by-step explanation:

Using Pythagoras' identity in the right triangle.

The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is

x² = 4² + 3² = 16 + 9 = 25 ( take the square root of both sides )

x = [tex]\sqrt{25}[/tex] = 5

Answer:

21

Step-by-step explanation:

you plug in 5 for a and 6 for b and solve.

The value of the expression 3 + (a + 4)(8 - b) when a = 5 and b = 6 is 21

3 + (a + 4)(8 - b)

when,

a = 5 and b = 6

= 3 + (5 + 4) (8 - 6)

= 3 + 9 (2)

= 3 + 18

= 21

Therefore, the value of the expression 3 + (a + 4)(8 - b) when a = 5 and b = 6 is 21

Learn more about evaluation:

https://brainly.com/question/4344214

#SPJ2

Answer:

-6.28576e+81

Step-by-step explanation:

Answer:

Answer is 9 Broski mark as brainliest

Step-by-step explanation:

Answer:

C

Step-by-step explanation:

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

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.

Answer: I think it is (D)

Step-by-step explanation: Its hard to explain but I hope this helps anyways!

Answer:

I think its D to so I would go with that

Answer:

721

Step-by-step explanation:

dog you in elementary school

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.

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

Answer:

$12,500 per year

Step-by-step explanation:

rate of change = change in dollars/change in years

So,

(245000 - 120000)/(2017 - 2007) = 125000/10 = $12,500 per year