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3 years ago

Can someone answer number 11?

Mathematics

2 answers:

Zinaida [17]3 years ago

6 0

1- rational 2- rational. Hope this helped!!

Anna71 [15]3 years ago

5 0

Answer:

Step-by-step explanation:

To be rational means to be able to express the result as the ratio of two whole numbers.

a) 4/7 + (-1/3) = 12/21 - 7/21 = 5/21 so rational

b) √(4) • 2/5 = ±2 • 2/5 = ±4/5 so both solutions are rational

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Pretty hard question

marishachu [46]

Answer:

Step-by-step explanation:

Take x = 1.

Now substitute in the function.

f(1) = 3 + √1

f(1) = 3 + 1

f(1) = 4

Now, we know the line of the function passes through 2 points : (0, 3) and (1, 4). Graph D shows these features.

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2 years ago

What value of x makes the equation 5(7x-3)-x=-4x-(-9-2x) true? please help :)

stiv31 [10]

X = 2/3 makes the equation true.

Answer: x = 2/3

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3 years ago

A tank has the shape of a surface generated by revolving the parabolic segment y = x2 for 0 ≤ x ≤ 3 about the y-axis (measuremen

Darina [25.2K]

Answer:

$100\pi\int\limits^9_0 {(\sqrt y)^2(14-y)} \, dy$ ft-lbs.

Step-by-step explanation:

Given:

The shape of the tank is obtained by revolving $y=x^2$ about y axis in the interval $0\leq x\leq 3$ .

Density of the fluid in the tank, $D=100\ lbs/ft^3$

Let the initial height of the fluid be 'y' feet from the bottom.

The bottom of the tank is, $y(0)=0^2=0$

Now, the height has to be raised to a height 5 feet above the top of the tank.

The height of top of the tank is obtained by plugging in $x=3$ in the parabolic equation . This gives,

$H=3^2=9\ ft$

So, the height of top of tank is, $y(3)=H=9\ ft$

Now, 5 ft above 'H' means $H+5=9+5=14$

Therefore, the increase in height of the top surface of the fluid in the tank is given as:

$\Delta y=(14-y)$ ft

Now, area of cross section of the tank is given as:

$A(y)=\pi r^2\\r\to radius\ of\ the\ cross\ section$

Radius is the distance of a point on the parabola from the y axis. This is nothing but the x-coordinate of the point.

We have, $y=x^2$

So, $x=\sqrt y$

Therefore, radius, $r=\sqrt y$

Now, area of cross section is, $A(y)=\pi (\sqrt y)^2$

Work done in pumping the contents to 5 feet above is given as:

$W=D\int\limits^{y(3)}_{y(0)} {A(y)(\Delta y)} \, dy$

Plug in all the values. This gives,

$W=100\int\limits^9_0 {\pi (\sqrt y)^2(14-y)} \, dy\\\\W=100\pi\int\limits^9_0 { (\sqrt y)^2(14-y)} \, dy\textrm{ ft-lbs}$

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2 years ago

Can someone helPPPPPPPPPPPPPPPPPP

andrezito [222]

I believe it’s option #3. hopefully that helps :)

4 0

2 years ago

Evaluate.<br> 4^3 + 8^2 = ??

katen-ka-za [31]

Answer: 128

Step-by-step explanation:

$4^3 = 4*4*4 = 16*4 = 64$

$8^2 = 8*8 = 64$

$64+64 = 128$

7 0

1 year ago

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