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2 years ago

What is the value of 3x3x3 +7(2x-6), when x=4

Mathematics

1 answer:

DIA [1.3K]2 years ago

3 0

Answer:

First can you use a * for the multiplication sign??

Step-by-step explanation:

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If a chair costs 734 dollars and I give it to my friend for 823 dollars how much is my profit as a percentage

kotegsom [21]

Answer:

$X=12.125\%$

Step-by-step explanation:

From the question we are told that:

Cost Price $CP=734$

Sale Price $SP=823$

Generally the equation for Profit P is mathematically given by

$Profit=SP-CP$

$P=823-734$

$P=89$

Therefore as a percentage

Percentage Profit X is given as

$X=\frac{89}{734}*100$

$X=12.125\%$

7 0

2 years ago

Find the area of the surface. the part of the hyperbolic paraboloid z = y2 − x2 that lies between the cylinders x2 + y2 = 4 and

Nadusha1986 [10]

Call the surface $S$ ; then the area of $S$ is given by the surface integral

$\displaystyle\iint_S\mathrm d\mathbf S$

Parameterize the surface by

$\mathbf r(u,v)=\begin{cases}x(u,v)=u\cos v\\y(u,v)=u\sin v\\z(u,v)=u^2\cos^2v-u^2\sin^2v=u^2\cos2v\end{cases}$

with $2\le u\le4$ and $0\le v\le2\pi$ . The surface element is given by

$\mathrm d\mathbf S=\|\mathbf r_u\times\mathbf r_v\|\,\mathrm du\,\mathrm dv$
$\mathrm d\mathbf S=u\sqrt{1+4u^2}\,\mathrm du\,\mathrm dv$

So the area is

$\displaystyle\iint_S\mathrm d\mathbf S=\int_{v=0}^{v=2\pi}\int_{u=2}^{u=4}u\sqrt{1+4u^2}\,\mathrm du\,\mathrm dv$
$=\displaystyle2\pi\int_{w=17}^{w=65}\sqrt w\,\frac{\mathrm dw}8$

where $w=1+4u^2\implies\mathrm dw=8u\,\mathrm du$

$=\displaystyle\frac\pi4\frac23w^{3/2}\bigg|_{w=17}^{w=65}$
$=\dfrac\pi6\left(65^{3/2}-17^{3/2}\right)\approx237.69$

8 0

2 years ago

Carol spends 17 hours in a 2-week period practicing her culinary skills. How many hours does she practice in 5 weeks?

Darina [25.2K]

Carol spends 52.5 hours practicing her culinary skills in a 5 week period.

17*2= 44 hours for 4 weeks
17/2= 8.5 for 1 week (half of 2 week period)
44+8.5= 52.5

6 0

3 years ago

Ms. johnson's class is having a pizza party. if there are 14 students and 7 pizzas cut into 8 slices, what answer choice represe

Lubov Fominskaja [6]

We are asked about the fraction of pizza each student gets, so the relevant numbers here is only 14 students and 7 pizzas. SO the fraction of pizza each student get is the ratio of the two:

fraction = 7 pizzas / 14 students

fraction = 1 / 2

<span>So each student gets 1/2</span>

8 0

2 years ago

Please help me with this question.

lara31 [8.8K]

The answer would be 66

3 0

2 years ago

Read 2 more answers