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3 years ago

6

a 15-ft ladder is leaning against one wall of an alley 9 ft wide. the ladder slips, its top sliding down the wall, its foot slid

ing across the alley and striking the opposite wall at a speed of 4 ft/sec. How fast is the top of the ladder falling at that instance?

1 answer:

blagie [28]3 years ago

5 0

2x dx/dt +2y dy/dt = 0
<span>x dx/dt + y dy/dt = 0 </span>
<span>9*4 + 12 dy/dt = 0 </span>
<span>dy/dt = - 3 ft/sec </span>

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The formula below is used to convert a tempreture in degrees Farenheit,F to a tempreture in degrees Celsuis ,C.C = 5/9 (f-32) Wh

spayn [35]

Answer:

4.4 degrees C.

Step-by-step explanation:

C = 5/9 (F - 32)

When F = 40:

C = 5/9( 40 - 32)

= 5/9 * 8

= 40/9

= 4.4 degrees C,

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2 years ago

Someone please help me on this one

irakobra [83]

12lb=$27
14lb=$x

$\frac{12}{27} = \frac{14}{x}$

cross multiply

12x=378
divide both sides by 12
x=31.5= $31.50

Answer=$31.50

8 0

3 years ago

An outlier always affects the mean.<br><br><br> True False

Ipatiy [6.2K]

Yes. If you have very high or very low outliers in your data set, it is generally preferred to use the median - the mid-point when all data points are arranged from least to greatest.

<span>A good example for when to avoid the mean and prefer the median is salary. The mean is less good here as there are a few very high salaries which skew the distribution to the right. This drags the mean higher to the point where it is disproportionately affected by the few higher salaries. In this case, the median would only be slightly affected by the few high salaries and is a better representation of the whole of the data. </span>

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3 0

4 years ago

Read 2 more answers

Write the point-slope form of the equation of the line that passes through the points (-8, 2) and (1, -4). Include your work in

Ymorist [56]

<h2>Greetings!</h2>

Answer:

y = $\frac{-2}{3}$ x - 4

Step-by-step explanation:

Firstly, you must find the gradient. This is found using the following formula:

$\frac{y2 - y1}{x2 - x1}$

Make sure that the x2 and y2 values are in the same coordinate set:

Let's set (-8 , 2) as y1 and x1, y1 = 2 and x1 = -8

That means that (1 , -4) is y2 and x2, y2 = -4 and x2 = 1

Plug the values in:

$\frac{-4-2}{1 - - 8}$

Simplified:

$\frac{-6}{9}$

Or -2/3

So the gradient is $\frac{-2}{3}$

Now, using the following equation of a line formula:

y - y1 = m(x - x1)

Where m is the gradient and y1 and x1 are two coordinates, we can plug these values in:

y1 = 2

x1 = -8

m = -2/3

y - 2 = 2/3(x - - 8)

We need to get rid of the two third fraction so we multiply the whole equation by three to cancel it out:

y * 3 = 3y

-2 * 3 = -6

-2/3 * 3 = -2

3y - 6 = -2(x - - 8)

The negative and the subtract makes it a positive:

3y - 6 = -2(x + 8)

Now we can multiply the bracket out:

-2 * x = -2x

8 * -2 = -18

So:

3y - 6 = -2x - 18

The slope form is usually:

y = mx + c

So we need to move the -6 over to the other side making it a positive 6:

3y = -2x -18 + 6

3y = -2x -12

Divide all the equation by three to get 1y:

y = $\frac{-2}{3}$ x - 4

Which is the equation!

<h2>Hope this helps!</h2>

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3 years ago

Read 2 more answers

Simplify this expression with only positive exponents.

Black_prince [1.1K]

Answer:

$\frac{2x}{y^{-1}}=2xy$

Step-by-step explanation:

To simplify the expression $\frac{2x}{y^{-1}}$ you must:

$\mathrm{Apply\:exponent\:rule}:\quad \:a^{-1}=\frac{1}{a}\\\\y^{-1}=\frac{1}{y}\\\\\frac{2x}{y^{-1}}=\frac{2x}{\frac{1}{y}}$

$\mathrm{Apply\:the\:fraction\:rule}:\quad \frac{a}{\frac{b}{c}}=\frac{a\cdot \:c}{b}\\\\\frac{2x}{\frac{1}{y}}=\frac{2xy}{1}$

$\mathrm{Apply\:the\:fraction\:rule}:\quad \frac{a}{1}=a\\\\\frac{2xy}{1} = 2xy$

Therefore,

$\frac{2x}{y^{-1}}=2xy$

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3 years ago