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3 years ago

What is the value of x in the equation 4 x plus 8 y equals 40, when y equals 0. 8? 4. 6 8. 4 10 12.

Mathematics

1 answer:

chubhunter [2.5K]3 years ago

3 0

Answer:

x = 8.4

Step-by-step explanation:

8 times 0.8 is 6.4, then 40 - 6.4 is 33.6, and 33.6 divided by 4 is 8.4

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The sale amount is 1,250.00, 5% sales tax.

Marina CMI [18]

Answer:

1250*.05=62.5. Then just add it to the amount for the total dollars shw needs to spend with tax

Step-by-step explanation:

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3 years ago

How do you solve 9r=3r+6

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9r=3r+6
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2 years ago

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Hannah has a biased coin.

muminat

Look at it this way:

When you flip a coin, the probability of it landing with EITHER side showing
is 100%.

This leads us to the rule ...

The sum of the probabilities of
all possible outcomes is 100%.

For a coin: (probability of heads) plus (probability of tails) = 100%.

That just says: We're 100% sure that the coin will land with either
heads or tails up.

An "honest" coin gets heads 50% of the time and tails the other 50%.

But if the coin is all bent and squashed and has a feather stuck to
one side and a wad of gum on the other side so that it comes up
heads 70% of the time, then the coin isn't 'honest'. But it still has to
land EITHER heads OR tails, so the sum of the probabilities is still 100%.

So the probability of heads is 30%.

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3 years ago

What is the answer in the remainder

ira [324]

Answer:

12 with a remainder of 5

Step-by-step explanation:

have a good day! :)

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2 years ago

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A rancher wishes to build a fence to enclose a 2250 square yard rectangular field. Along one side the fence is to be made of hea

Bess [88]

Answer:

The least cost of fencing for the rancher is $1200

Step-by-step explanation:

Let x be the width and y the length of the rectangular field.

Let C the total cost of the rectangular field.

The side made of heavy duty material of length of x costs 16 dollars a yard. The three sides not made of heavy duty material cost $4 per yard, their side lengths are x, y, y. Thus

$C=4x+4y+4y+16x\\C=20x+8y$

We know that the total area of rectangular field should be 2250 square yards,

$x\cdot y=2250$

We can say that $y=\frac{2250}{x}$

Substituting into the total cost of the rectangular field, we get

$C=20x+8(\frac{2250}{x})\\\\C=20x+\frac{18000}{x}$

We have to figure out where the function is increasing and decreasing. Differentiating,

$\frac{d}{dx}C=\frac{d}{dx}\left(20x+\frac{18000}{x}\right)\\\\C'=20-\frac{18000}{x^2}$

Next, we find the critical points of the derivative

$20-\frac{18000}{x^2}=0\\\\20x^2-\frac{18000}{x^2}x^2=0\cdot \:x^2\\\\20x^2-18000=0\\\\20x^2-18000+18000=0+18000\\\\20x^2=18000\\\\\frac{20x^2}{20}=\frac{18000}{20}\\\\x^2=900\\\\\mathrm{For\:}x^2=f\left(a\right)\mathrm{\:the\:solutions\:are\:}x=\sqrt{f\left(a\right)},\:\:-\sqrt{f\left(a\right)}\\\\x=\sqrt{900},\:x=-\sqrt{900}\\\\x=30,\:x=-30$

Because the length is always positive the only point we take is $x=30$ . We thus test the intervals $(0, 30)$ and $(30, \infty)$

$C'(20)=20-\frac{18000}{20^2} = -25 < 0\\\\C'(40)= 20-\frac{18000}{20^2} = 8.75 >0$

we see that total cost function is decreasing on $(0, 30)$ and increasing on $(30, \infty)$ . Therefore, the minimum is attained at $x=30$ , so the minimal cost is

$C(30)=20(30)+\frac{18000}{30}\\C(30)=1200$

The least cost of fencing for the rancher is $1200

Here’s the diagram:

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3 years ago