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3 years ago

Simplify (30x - 12y) + (41x + 62y)

Mathematics

2 answers:

Taya2010 [7]3 years ago

8 0

Answer:

71x+50y

Step-by-step explanation:

DedPeter [7]3 years ago

7 0

Answer is: 71x+50y
(by simplifying) :)

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The numbers are {0, 1, 2, 3, 4, ...}. whole rational natural real integer

Brilliant_brown [7]

Answer:

Whole numbers are all natural numbers including 0 e.g. 0, 1, 2, 3, 4…

Integers include all whole numbers and their negative counterpart e.g. …-4, -3, -2, -1, 0,1, 2, 3, 4,…

Step-by-step explanation:

7 0

3 years ago

9x43=9x(40+3)=(9x )+(9x3)= +27=

denis-greek [22]

Answer:

387, or you can do it another way in the problem if you like/.

Step-by-step explanation:

3x9=27

4x9=36

36+2=38

387

8 0

3 years ago

2.Solve the following quadratic equations i. 9x^2 - 1/16 ii. 2h^2 - 3h - 27

Juli2301 [7.4K]

$i)~9x^2-\dfrac{1}{16}=0\iff9x^2=\dfrac{1}{16}\iff x^2=\dfrac{1}{9\cdot16}\iff \\\\x^2=\dfrac{1}{144}\iff x=\pm\sqrt{\dfrac{1}{144}}=\pm\dfrac{1}{12}\Longrightarrow\boxed{x=\pm\dfrac{1}{12}}$

$ii)~2h^2-3h-27=0\\\\\Delta=b^2-4ac\to \Delta=(-3)^2-4\cdot2\cdot(-27)\to\Delta=9+216=225\\\\
\Longrightarrow h=\dfrac{-b\pm\sqrt{\Delta}}{2a}=\dfrac{-(-3)\pm\sqrt{225}}{2\cdot2}=\dfrac{3\pm15}{4}\\\\\begin{cases}h_1=\dfrac{3+15}{4}=\dfrac{18}{4}\iff \boxed{h_1=\dfrac{9}{2}}\\h_2=\dfrac{3-15}{4}=\dfrac{-12}{4}\iff\boxed{h_2=-3}\end{cases}$

4 0

3 years ago

A sphere of radius r is cut by a plane h units above the equator, where

Anika [276]

Consider the top half of a sphere centered at the origin with radius $r$ , which can be described by the equation

$z=\sqrt{r^2-x^2-y^2}$

and consider a plane

$z=h$

with $0$ . Call the region between the two surfaces $R$ . The volume of $R$ is given by the triple integral

$\displaystyle\iiint_R\mathrm dV=\int_{-\sqrt{r^2-h^2}}^{\sqrt{r^2-h^2}}\int_{-\sqrt{r^2-h^2-x^2}}^{\sqrt{r^2-h^2-x^2}}\int_h^{\sqrt{r^2-x^2-y^2}}\mathrm dz\,\mathrm dy\,\mathrm dx$

Converting to polar coordinates will help make this computation easier. Set

$\begin{cases}x=\rho\cos\theta\sin\varphi\\y=\rho\sin\theta\sin\varphi\\z=\rho\cos\var\phi\end{cases}\implies\mathrm dx\,\mathrm dy\,\mathrm dz=\rho^2\sin\varphi\,\mathrm d\rho\,\mathrm d\theta\,\mathrm d\varphi$

Now, the volume can be computed with the integral

$\displaystyle\iiint_R\mathrm dV=\int_0^{2\pi}\int_0^{\arctan\frac{\sqrt{r^2-h^2}}h}\int_{h\sec\varphi}^r\rho^2\sin\varphi\,\mathrm d\rho\,\mathrm d\varphi\,\mathrm d\theta$

You should get

$\dfrac{2\pi}3\left(r^3\arctan\dfrac{\sqrt{r^2-h^2}}h-\dfrac{h^3}2\left(\dfrac{r\sqrt{r^2-h^2}}{h^2}+\ln\dfrac{r+\sqrt{r^2-h^2}}h\right)\right)$

5 0

3 years ago

Please help me with this problem

sineoko [7]

Answer:

$4$

Step-by-step explanation:

$\frac{ {3x}^{2} -2x + 7}{2x+5} \\ \frac{3( - 1) {}^{2} - 2( - 1) + 7}{2( - 1) + 5 } \\ \frac{3 + 2 + 7}{ - 2 + 5} \\ \frac{12}{3} = 4$

7 0

3 years ago