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3 years ago

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A rectangular swimming pool is 6 ft deep. One side of the pool is 4.5 times longer than the other. The amount of water needed to

fill the swimming pool is 3888 cubic feet. Find the dimensions of the pool.

2 answers:

nydimaria [60]3 years ago

5 0

<u>Answer: </u>

Dimension of pool are length = 12 feet, width = 54 feet and depth = 6 feet.

<u>Solution : </u>

Need to find dimensions of a swimming pool.

Depth of pool = 6 feet

Given that one side of the pool is 4.5 times longer than other.

Let’s say width of pool = x

So other side that is length of the pool = 4.5x

$\text { Volume of cuboid }=\text { length } \times \text { width } \times \text { depth }$

$\text { volume of swimming pool }=6 \times x \times 4.5 x$

volume of pool = $27 x^{2}$ --- eqn 1

Also given that amount of water needed to fill the pool is 3888 cubic feet that is volume of pool is 3888 cubic feet. Substituting volume in equation (1)

$3888=27 x^{2}$

Now solving above equation for x.

$x^{2}=\frac{3888}{27}=144=12^{2}$

so x = 12

so width of pool = x = 12 feet

By substituting the value of “x” we get length of pool

And length of pool = 4.5x = 4.5 $\times$ 12 = 54 feet

Hence dimension of pool are length = 12 feet, width = 54 feet and depth = 6 feet.

Murljashka [212]3 years ago

4 0

Answer:

162

Step-by-step explanation:

6*4.5=27

6*27=162

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asambeis [7]

Answer:

87 many more plums are there in Basket A than Basket B

Step-by-step explanation:

Before

N = 58/2

Basket A = N x 7 + 58

Basket B = N x 7

Now

Basket A = 29 x 7 + 58

= 261/3

= 87

Basket B = 29 x 7

= 203 + 58

= 261/3

= 87

Basket A and B has a difference of 87 Plums

:) Thank you!!

4 0

3 years ago

Can someone thoroughly explain this implicit differentiation with a trig function. No matter how many times I try to solve this,

Anton [14]

Answer:

$\frac{dy}{dx}=y'=\frac{\sec^2(x-y)(8+x^2)^2+2xy}{(8+x^2)(1+\sec^2(x-y)(8+x^2))}$

Step-by-step explanation:

So we have the equation:

$\tan(x-y)=\frac{y}{8+x^2}$

And we want to find dy/dx.

So, let's take the derivative of both sides:

$\frac{d}{dx}[\tan(x-y)]=\frac{d}{dx}[\frac{y}{8+x^2}]$

Let's do each side individually.

Left Side:

We have:

$\frac{d}{dx}[\tan(x-y)]$

We can use the chain rule, where:

$(u(v(x))'=u'(v(x))\cdot v'(x)$

Let u(x) be tan(x). Then v(x) is (x-y). Remember that d/dx(tan(x)) is sec²(x). So:

$=\sec^2(x-y)\cdot (\frac{d}{dx}[x-y])$

Differentiate x like normally. Implicitly differentiate for y. This yields:

$=\sec^2(x-y)(1-y')$

Distribute:

$=\sec^2(x-y)-y'\sec^2(x-y)$

And that is our left side.

Right Side:

We have:

$\frac{d}{dx}[\frac{y}{8+x^2}]$

We can use the quotient rule, where:

$\frac{d}{dx}[f/g]=\frac{f'g-fg'}{g^2}$

f is y. g is (8+x²). So:

$=\frac{\frac{d}{dx}[y](8+x^2)-(y)\frac{d}{dx}(8+x^2)}{(8+x^2)^2}$

Differentiate:

$=\frac{y'(8+x^2)-2xy}{(8+x^2)^2}$

And that is our right side.

So, our entire equation is:

$\sec^2(x-y)-y'\sec^2(x-y)=\frac{y'(8+x^2)-2xy}{(8+x^2)^2}$

To find dy/dx, we have to solve for y'. Let's multiply both sides by the denominator on the right. So:

$((8+x^2)^2)\sec^2(x-y)-y'\sec^2(x-y)=\frac{y'(8+x^2)-2xy}{(8+x^2)^2}((8+x^2)^2)$

The right side cancels. Let's distribute the left:

$\sec^2(x-y)(8+x^2)^2-y'\sec^2(x-y)(8+x^2)^2=y'(8+x^2)-2xy$

Now, let's move all the y'-terms to one side. Add our second term from our left equation to the right. So:

$\sec^2(x-y)(8+x^2)^2=y'(8+x^2)-2xy+y'\sec^2(x-y)(8+x^2)^2$

Move -2xy to the left. So:

$\sec^2(x-y)(8+x^2)^2+2xy=y'(8+x^2)+y'\sec^2(x-y)(8+x^2)^2$

Factor out a y' from the right:

$\sec^2(x-y)(8+x^2)^2+2xy=y'((8+x^2)+\sec^2(x-y)(8+x^2)^2)$

Divide. Therefore, dy/dx is:

$\frac{dy}{dx}=y'=\frac{\sec^2(x-y)(8+x^2)^2+2xy}{(8+x^2)+\sec^2(x-y)(8+x^2)^2}$

We can factor out a (8+x²) from the denominator. So:

$\frac{dy}{dx}=y'=\frac{\sec^2(x-y)(8+x^2)^2+2xy}{(8+x^2)(1+\sec^2(x-y)(8+x^2))}$

And we're done!

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3 years ago

1. Mr. Hudson bought some shirts for the new members of his band. The cost for the number of shirts, including $3.99 shipping, w

nignag [31]

Answer:

6x + 4 - 1/100 = 77.5

Step-by-step explanation:

Inc shipping all shirts 77.49

Shirt individual cost = 12.25

We find the division first = 77.49-3.99 = 73.5 = 73 1/2

Then we divide 73.5 / 12.25 = 6

Then we have our equation

6x + 4 - 1/100 = 77.5

7 0

3 years ago

Victoria recently switched to a new electric company. If she uses between 0 and 400 kilowatt-hours (kWh) of electricity per mont

Gekata [30.6K]

Answer:

see the explanation

Step-by-step explanation:

<em><u>The question is </u></em>

Identify the domain and the range, using words and inequalities

Let

x -----> the number of kilowatt-hours (kWh) of electricity per month

y ----> the price per month

we know that

Part 1) For the value of x between 0 kWh and 400 kWh

$0\ kWh \leq x < 400\ kWh$

The price is equal to

$y=\$30$

therefore

The domain is the interval ------> [0,400)

The domain is all real numbers greater than or equal to 0 kWh and less than 400 kWh

The range is ($30)

The range is equal to $30

Part 2) For the value of x equal to 400 kWh or more per month

$x\geq 400\ kWh$

The domain is the interval -----> [400, infinite)

The domain is all real numbers greater than or equal to 400 kWh

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$y=0.097x$

<em>Find the range</em>

For x=400 kWh

$y=0.097(400)=\$38.8$

so

$y\geq \$38.8$

The range is the interval -----> [38.8, infinite)

7 0

3 years ago

A ball is thrown vertically upward from the ground with an initial velocity of 111 ft/sec. Use the quadratic function h(t) = −16

ddd [48]

Answer:

t=3.5 seconds

Step-by-step explanation:

Given

h(t) = −16t^2 + 111t + 0

h'(t)= -32t + 111

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h(t)= -32t + 111=0

-32t + 111=0

-32t=-111

Divide both sides by -32

t=3.46872

Approximately, t=3.5 seconds

Recall,

Maximum height occurs when h(t) = 0

h(t)= -32t + 111=0

= -32(3.46872)+111

= -110.99904+111

= 0.00096 ft

4 0

2 years ago