Please help im begging you

Find the domain of the function expressed by the formula:
y = 1/x - 7

Answer:

A. 1 + 3x = -89

B. x = -30

Step-by-step explanation:

Let the unknown variable be x.

A. Translating the word problem into an algebraic expression, we have;

1 + 3x = -89

B. To solve for the unknown variable;

1 + 3x = -89

3x = -89 -1

3x = -90

x = -90/3

x = -30

Check:

1 + 3x = -89

Substituting the value of x;

1 + 3(-30) = -89

1 + (-90) = -89

1 - 90 = -89

-89 = -89

9514 1404 393

Answer:

  1/2 year

Step-by-step explanation:

Put the numbers into the interest formula and solve for t.

  I = Prt

  8100 = 180000(0.09)t

  t = 8100/16200 = 1/2

It will take 1/2 year to earn N8100 in interest at 9%.

Answer:

The 95% confidence interval for the mean time for all players, in minutes, is: (7.95, 11.01).

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom,which is the sample size subtracted by 1. So

df = 10 - 1 = 9

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 9 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.2622.

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 2.2622\frac{2.14}{\sqrt{10}} = 1.53[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 9.48 - 1.53 = 7.95 minutes.

The upper end of the interval is the sample mean added to M. So it is 9.48 + 1.53 = 11.01 minutes.

The 95% confidence interval for the mean time for all players, in minutes, is: (7.95, 11.01).

Answer:

84°

Step-by-step explanation:

the total angle in a straight line sum up to 180°

Answer:

a) 0.9544 = 95.44% of scores lie between 220 and 380 points.

b) 0.1587 = 15.87% probability that a randomly chosen student scores is below 260.

c) 25.14% of scores are above 326.8 points.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean of 300 and a standard deviation of 40.

This means that [tex]\mu = 300, \sigma = 40[/tex]

(a) What proportion of scores lie between 220 and 380 points?

This is the p-value of Z when X = 380 subtracted by the p-value of Z when X = 220.

X = 380

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{380 - 300}{40}[/tex]

[tex]Z = 2[/tex]

[tex]Z = 2[/tex] has a p-value of 0.9772.

X = 220

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{220 - 300}{40}[/tex]

[tex]Z = -2[/tex]

[tex]Z = -2[/tex] has a p-value of 0.0228.

0.9772 - 0.0228 = 0.9544

0.9544 = 95.44% of scores lie between 220 and 380 points.

(b) What is the probability that a randomly chosen student scores is below 260?

This is the p-value of Z when X = 260. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{260 - 300}{40}[/tex]

[tex]Z = -1[/tex]

[tex]Z = -1[/tex] has a p-value of 0.1587.

0.1587 = 15.87% probability that a randomly chosen student scores is below 260.

(c) What percent of scores are above 326.8 points?

The proportion is 1 subtracted by the p-value of Z when X = 326.8. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{326.8 - 300}{40}[/tex]

[tex]Z = 0.67[/tex]

[tex]Z = 0.67[/tex] has a p-value of 0.7486.

1 - 0.7486 = 0.2514

0.2514*100% = 25.14%

25.14% of scores are above 326.8 points.

Answer:

-7.5

Alternatively,

-0.5(units^-1) + (-4(units^0)) + (-3(units))

Step-by-step explanation:

On graph, only clearly defined points:

1. x = -3 , y = 0

2. x = -3 , y = -8

3. x = 5 , y = -4

So for:

1. -3 = c ( + a×(0^2) + b×0)

And

2. -3 = a×((-8)^2) + b×(-8) + c = 64×a + (-8)×b + c

Since c = -3 ==> 64×a - 8×b = 0

Simplified ==> 8×a - b = 0 ==> b = 8×a

3. 5 = a×((-4)^2) + b×(-4) + c = 16×a + (-4)×b + c

Since c = -3 ==> 16×a - 4×b = 5 - (-3) = 8

Simplified ==> 4×a - b = 2

Since b = 8×a ==> 4×a - (8×a) = 2

Simplified ==> 2×a - 4×a = 1

==> -2×a = 1

==> a = -0.5

Since b = 8×a ==> b = 8×(-0.5) = -4

So...

c = -3

b = -4

a = -0.5

Then...

a + b + c = -0.5 - 4 - 3 = -7.5

Answer: [tex]y=\frac{1}{3}x+\frac{13}{3}[/tex]

Step-by-step explanation:

(slope = m)

[tex]m=\frac{y_2-y_1}{x_2-x_1}=\frac{4-6}{-1-5}=\frac{-2}{-6}=\frac{1}{3}[/tex]

[tex]y=mx+b, (5,6), (-1,4), m=\frac{1}{3}[/tex]

[tex]y=mx+b\\6=\frac{1}{3}(5)+b\\b=6-\frac{5}{3} \\b=\frac{13}{3}\\y=\frac{1}{3}x+\frac{13}{3}[/tex]

Answer:

We Reject the Null, H0 and conclude that the volume of juice filled by old machine varies more than volume filled by new machine

Step-by-step explanation:

Given the data:

Old machine: 8.2, 8.0, 7.9, 7.9, 8.5, 7.9, 8.1,8.1, 8.2, 7.9

Sample size, n = 10

Using calculator :

s1² = 0.37889.

New machine: 8.0, 8.1, 8.0, 8.1, 7.9, 8.0, 7.9, 8.0, 8.1

Sample size, n = 9

s2² = 0.006111

Hypothesis :

H0 : s1² = s2²

H1 : s1² > s2²

New machine :

s2² = 0.006111 ; n = 9

Using the Ftest :

Ftest statistic = larger sample variance / smaller sample variance

Ftest statistic = 0.37889 / 0.006111

Ftest statistic = 62.0

Decision region :

Reject H0 ; If Test statistic > Critical value

The FCritical value at 0.05

DFnumerator = 10 - 1 = 9

DFdenominator = 9 - 1 = 8

Fcritical(0.05, 9, 8) = 3.388

Since 62 > 3.388 ; Reject H0 and conclude that volume filled by old machine varies more than volume filled by new machine

Answer:

b

Step-by-step explanation:

The value of x 85.

The arc period of a circle can be calculated with the radius and relevant perspective using the arc period method.

⇒angle= arc/radius

⇒  107°=arc/7

⇒ arc =1o7°*7

⇒arc=107π/180° *7

⇒arc = 85

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Answer:

184.8

Step-by-step explanation:

y =kx

k=y/x

k=42/5=8.4

y=8.4*22

Answer:

325 pencils, 650 markers, 975 pens.

Answer:

no solution

Step-by-step explanation:

a negative number cannot be square rooted

Answer:

"not possible". no such thing as a negative squared number

Answer:

[tex]15y^9 - 7y^3 + y[/tex]

Nonic polynomial

Step-by-step explanation:

Given

[tex]y - 7y^3 + 15y^9[/tex]

Required

Write in standard form

The standard form of a polynomial is:

[tex]ay^n + by^{n-1} + ......... + k[/tex]

So, we have:

[tex]y - 7y^3 + 15y^9[/tex]

The standard form is:

[tex]15y^9 - 7y^3 + y[/tex]

And the name is: Nonic polynomial (because it has a degree of 9)

==========================================================

Explanation:

area of rectangle = L*W = 129

L*W = 129

x*(2x-9) = 129

2x^2-9x = 129

2x^2-9x-129 = 0

Apply the quadratic formula. We'll use a = 2, b = -9, c = -129.

[tex]x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x = \frac{-(-9)\pm\sqrt{(-9)^2-4(2)(-129)}}{2(2)}\\\\x = \frac{9\pm\sqrt{1113}}{4}\\\\x \approx \frac{9\pm33.36165464}{4}\\\\x \approx \frac{9+33.36165464}{4}\ \text{ or } \ x \approx \frac{9-33.36165464}{4}\\\\x \approx \frac{42.36165464}{4}\ \text{ or } \ x \approx \frac{-24.36165462}{4}\\\\x \approx 10.59041366\ \text{ or } \ x \approx -6.09041364\\\\[/tex]

We ignore the negative solution because a negative length makes no sense.

The length is approximately L = 10.5904 cm.

The width is 2L-9 = 2*10.5904-9 = 12.1808 cm approximately.

As a quick check,

L*W = 10.5904*12.1808 = 128.99954432

which isn't too far off from 129. We have rounding error which is why we don't perfectly land on the target area value. If you wanted to get closer to the value 129, then use more decimal digits in the approximations of L and W.

----------------------------

If you draw a diagonal in the rectangle, then you form two identical or congruent right triangles.

Focusing on one of those triangles, we have

Apply the pythagorean theorem

a^2+b^2 = c^2

c = sqrt( a^2 + b^2 )

c = sqrt( (10.5904)^2 + (12.1808)^2 )

c = 16.1408940520653

c = 16.14

The diagonal is roughly 16.14 cm long.

Answer:

We have 60% salt and 85% salt solutions and we need 140 ounces of a solution that is 80% salt.

We set up 2 equations:

A) x + y = 140

B) .60x + .85y = .80 * 140

Multiply equation A) by -.60

A) -.60x -.60y = -84  then we add this to B)

B) .60x + .85y = 112

.25y = 28

y = 112 ounces of 85% salt

x = 28 ounces of 60% salt.

Double Check

112 * .85 = 95.2 AND 28 * .60 = 16.80

95.2 + 16.80 = 112

and 112/140 = 80 per cent!!

Source: http://www.1728.org/mixture.htm

Step-by-step explanation:

Answer:

0.5675 = 56.75% probability that at least 22 of the 44 students selected are non-history majors.

Step-by-step explanation:

The students are chosen without replacement from the sample, which means that the hypergeometric distribution is used to solve this question. We are working also with a sample with more than 10 history majors and 10 non-history majors, which mean that the normal approximation can be used to solve this question.

Hypergeometric distribution:

The probability of x successes is given by the following formula:

[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]

In which:

x is the number of successes.

N is the size of the population.

n is the size of the sample.

k is the total number of desired outcomes.

Combinations formula:

[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Approximation:

We have to use the mean and the standard deviation of the hypergeometric distribution, that is:

[tex]\mu = \frac{nk}{N}[/tex]

[tex]\sigma = \sqrt{\frac{nk(N-k)(N-n)}{N^2(N-1)}}[/tex]

In this question:

88 + 88 = 176 students, which means that [tex]N = 176[/tex]

88 non-history majors, which means that [tex]k = 88[/tex]

44 students are selected, which means that [tex]n = 44[/tex]

Mean and standard deviation:

[tex]\mu = \frac{44*88}{176} = 22[/tex]

[tex]\sigma = \sqrt{\frac{44*88*(176-88)*(176-44)}{176^2(175-1)}} = 2.88[/tex]

What is the probability that at least 22 of the 44 students selected are non-history majors?

Using continuity correction, as the hypergeometric distribution is discrete and the normal is continuous, this is [tex]P(X \geq 22 - 0.5) = P(X \geq 21.5)[/tex], which is 1 subtracted by the p-value of Z when X = 21.5. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{21.5 - 22}{2.88}[/tex]

[tex]Z = -0.17[/tex]

[tex]Z = -0.17[/tex] has a p-value of 0.4325

1 - 0.4325 = 0.5675

0.5675 = 56.75% probability that at least 22 of the 44 students selected are non-history majors.

Answer:

2k-3

Step-by-step explanation:

the square of k is k times k so 2k (two times k) and less than three means minus three.

Answer:

Pencils = 325 ; Pens = 975 ; Markers = 650

Step-by-step explanation:

Let :

Number of Pencils = x

Number of pens = y

Number of markers = z

2 times as many markers as pencils

z = 2x

3 times as many pens as pencils

y = 3x

x + y + z = 1950

Write z and y in terms of x in the equation :

x + 3x + 2x = 1950

6x = 1950

Divide both sides by 6

6x / 6 = 1950 / 6

x = 325

Number of pencils = 325

Pens = 3 * 325 = 975

Markers = 2 * 325 = 650

Pencils = 325 ; Pens = 975 ; Markers = 650

Answer:

speaking giberish

Step-by-step explanation:

cos it is just a word that is rare

Answer:5

Step-by-step explanation:

Where the above parameters are given,  you need to walk a distance of approximately √41 miles back to your car.

To calculate the total distance you need to walk, you can use the Pythagorean theorem since you have a right triangle formed by the north and east displacements.

Distance = √((Distance north)² + (Distance east)²)

= √((5 miles)² + (4 miles)²)

= √(25 miles + 16 miles)

= √41 miles

Hence, you need to walk a distance of  approximately √41 miles back to your car.

As for the direction, based on the net displacements, you are 5 miles north and 4 miles east of your car, so the direction would be a combination of north and east, often referred to as northeast.

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I cant graph it on here but. if your graph goes by 10 then the slope should increase by 666 every minute on the x line

Answer:

The answer is in the screenshot

Step-by-step explanation:

PLEASE GIVE BRAINLIEST

Answer:

Hence, MEAN OF FIRST FIVE COMPOSITE NOS IS 7.5

Answer:

ask in English then I can help u

Base case (n = 1):

• left side = 1×2² = 4

• right side = 1×(1 + 1)×(3×1² + 11×1 + 10)/12 = 4

Induction hypothesis: Assume equality holds for n = k, so that

1×2² + 2×3² + 3×4² + … + k × (k + 1)² = k × (k + 1) × (3k ² + 11k + 10)/12

Induction step (n = k + 1):

1×2² + 2×3² + 3×4² + … + k × (k + 1)² + (k + 1) × (k + 2)²

= k × (k + 1) × (3k ² + 11k + 10)/12 + (k + 1) × (k + 2)²

= (k + 1)/12 × (k × (3k ² + 11k + 10) + 12 × (k + 2)²)

= (k + 1)/12 × ((3k ³ + 11k ² + 10k) + 12 × (k ² + 4k + 4))

= (k + 1)/12 × (3k ³ + 23k ² + 58k + 48)

= (k + 1)/12 × (3k ³ + 23k ² + 58k + 48)

On the right side, we want to end up with

(k + 1) × (k + 2) × (3 (k + 1) ² + 11 (k + 1) + 10)/12

which suggests that k + 2 should be factor of the cubic. Indeed, we have

3k ³ + 23k ² + 58k + 48 = (k + 2) (3k ² + 17k + 24)

and we can rewrite the remaining quadratic as

3k ² + 17k + 24 = 3 (k + 1)² + 11 (k + 1) + 10

so we would arrive at the desired conclusion.

To see how the above rewriting is possible, we want to find coefficients a, b, and c such that

3k ² + 17k + 24 = a (k + 1)² + b (k + 1) + c

Expand the right side and collect like powers of k :

3k ² + 17k + 24 = ak ² + (2a + b) k + a + b + c

==>   a = 3   and   2a + b = 17   and   a + b + c = 24

==>   a = 3, b = 11, c = 10

Answer:

f(x) can not be equal to g(x)

Step-by-step explanation:

If the result is possible:

f(x) = g(x)

x + 8 = x + 2

x + 8 - (x + 2) = x + 2 - (x + 2)

6 = 0

Because 6 can't be equal to 0, so do f(x) can't be equal to g(x)

Answer:

y=-1/2x+-1

Step-by-step explanation:

try desmos with this equation.

y=mx+b

m=the slope which is -1/2. It goes down 1 it is negative because it is going down, and to the right 2.

b=y-intercept meaning the point which the line crosses the line y .-1

Answer:

y = d + a · cos(bx - c) ⇒ y = -4cos(4/3x)

Amplitude = |a| = |-4| = 4

Period = [tex]\frac{2\pi }{b} =\frac{2\pi }{\frac{4}{3} } =2\pi *\frac{3}{4} =\frac{3}{2} \pi[/tex]