please help me guys anyone

Answer:

B

Given equation: \(x^2 = -8x -7\)

To solve the quadratic equation, we will need to set one side of the equation equal to 0. This can be done by subtracting x² on both sides.

\(\implies x^2 - x^2= -8x -7 - x^2\)

\(\implies 0= -8x -7 - x^2\)

To further simplify, we can factor -1 from the expression on the R.H.S. Then, we can cancel the -1 since there is a 0 on the other side.

\(\implies 0= -1(8x + 7 + x^2)\)

\(\implies 0= 8x + 7 + x^2 = x^2 + 8x + 7\)

Finally, factor the expression on the right hand side.

Factoring a quadratic equation can be done in 2 ways.

In this method, we split the middle term into two suitable terms. The suitable terms must follow two conditions.

Then, we factor the first two terms of the expression and the last two terms of the expression. Eventually, we will get a common expression. So, we can further factorize to get a product of two expressions.

In this method, we will compare our equation with the standard form equation to determine the a, b, and c variables. Then, we plug the variables into the formula and simplify to get the roots (solutions).

\(\text{Quadratic Formula:} \ \dfrac{-b\ \± \sqrt{b^{2} - 4ac} }{2a}\)

We can use any method to solve for the roots. First, let us check whether the middle term could be split into two suitable terms such that those terms could meet the criteria stated above.

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

We can see that 8x is the middle term and it can be split into the sum of 7x and x. The product of the (middle term) coefficients is 7. The product of the coefficients (first and last terms) is also 7. Since both products match, we can use the splitting method to factorize the expression.

\(\implies 0= x^2 + 8x+ 7\)

\(\implies 0= x^2 + x + 7x+ 7\)

Now, factor the first two terms and the last two terms separately.

\(\implies 0= x^2 + x + 7x+ 7\)

\(\implies 0= x(x + 1) + 7(x+ 1)\)

We can see a common expression. Finally, let us factor the common expression to get a product of two expressions.

\(\implies 0= (x + 7)(x + 1)\)

Since the factorized expression equals to 0, we can set each expression (inside the parentheses) equal to 0.

\(\implies x + 7 = 0; x + 1 = 0\)

\(\implies x = -7; x = -1\)

Now, let us try to solve using the Quadratic formula.

\(0= x^2 + 8x+ 7\)

Tip: Standard form: 0 = ax² + bx + c

Comparing both equations will allow us to determine the a, b, c variables.

⇒ a = 1; b = 8; c = 7

Now, let us plug these values into the quadratic formula and simplify.

\(\implies \dfrac{-b\ \± \sqrt{b^{2} - 4ac} }{2a}\)

\(\implies \dfrac{-8\ \± \sqrt{8^{2} - 4(1)(7)} }{2(1)}\)

\(\implies \dfrac{-8\ \± \sqrt{64 - 28} }{2}\)

\(\implies \dfrac{-8\ \± \sqrt{36}}{2} = \dfrac{-8\± 6}{2} = \dfrac{-8 + 6}{2},\ \dfrac{-8 - 6}{2} = \dfrac{-2}{2} ,\ \dfrac{-14}{2} = -1 , -7 \ \text{(B)}\)

Therefore, in both methods, the answer is -1, -7 (B).

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a. The table value of z 0.99 is given as 2.58.

b. we use σ = 2.30 minutes.

c. The value of Z is given as 0.609.

d. The confidence interval is (23.391, 24.609) minutes.

a) To find the z-score for a 0.99 confidence interval, we need to find the z-score that leaves 0.5% (since it's two-tailed, we split the 1% or 0.01 of the data that's not within the confidence interval into two) in each tail. The z-score for 0.995 (0.5% in the upper tail) is approximately 2.58 in standard normal distribution tables. So, Z_0.99 is 2.58.

b) Therefore, we use σ = 2.30 minutes.

c) The standard error of the mean (SE) is given by σ/√n, where n is the sample size.

Here, σ = 2.30 minutes and n = 95.

Therefore, SE = σ/√n

= 2.30/√95

= 0.236 minutes.

Multiply this by the z-score to find Z * σ/√n.

Therefore, Z * σ/√n = 2.58 * 0.236 ≈ 0.609.

d) The 0.99 confidence interval for μ

Here, x is the sample mean which is 24 minutes.

So the confidence interval is approximately

= (24 - 0.609, 24 + 0.609)  

= (23.391, 24.609) minutes.

This is the range of values we are 99% confident that the true population mean (μ) falls in.

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Answer:

1/27

plz mark brainest

Step-by-step explanation:

Answer:

1/27

Step-by-step explanation:

1/3 ^3 is 1.27

You take 1 ^3= 1

And 3^3 = 27

and make it 1/27

Answer:

i got banned and i got -7 pts i hope you understand

Step-by-step explanation:

The wind has a magnitude of approximately 20.25 km/h and is blowing in a direction approximately 56.31° east of south. Magnitude is the hypotenuse of a right triangle with westerly and southerly components.

To find the magnitude and direction of the wind with a westerly component of 11 km/h and a southerly component of 17 km/h, we can use the Pythagorean theorem and trigonometry.

The magnitude of the wind is given by the hypotenuse of a right triangle with legs 11 km/h and 17 km/h. Using the Pythagorean theorem, we get:

magnitude = \(\sqrt{(11^2 + 17^2)} \approx 20.25 \;km/h\)

To find the direction of the wind, we can use trigonometry. The angle θ between the wind direction and the east direction can be found using the inverse tangent function:

\(tan(\theta)\) = opposite/adjacent = 17/11

\(\theta = atan(17/11) \approx 56.31^{\circ}\)

Therefore, the wind has a magnitude of approximately 20.25 km/h and is blowing in a direction approximately 56.31° east of south.

In summary, to find the magnitude and direction of wind with given westerly and southerly components, we can use the Pythagorean theorem and trigonometry.

The magnitude is given by the hypotenuse of a right triangle with legs equal to the westerly and southerly components, while the direction is given by the angle between the wind direction and the east direction, which can be found using the inverse tangent function.

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It's difficult to say whether the conditions for constructing a t-confidence interval are met based on the information provided. To construct a t-confidence interval, three conditions must be met:

The sampling method must be random. It's not specified in the problem whether the method of selecting the vehicles was random or not, so it's impossible to say whether this condition is met.

The sample size must be large enough. A sample size of 100 vehicles is considered to be large enough for the normal/large sample condition to be met.

The population must be approximately normally distributed or the sample size must be large. Since the problem does not specify anything about the distribution of the population, it is not clear if this condition is met.

Given that the information provided does not give enough details to state whether the conditions for constructing a t-confidence interval are met or not.

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From the given function f(x) the value of expression f(f(81)) is equal to 3.

Let's see how to find the answer to the question:

Find (f0f)(81)

In the given question, we need to find the value of (f0f)(81). This notation means (f◦f)(81).

Given that f(x)= sqrt(x) and g(x) =\((x - 7)^2\).

We know that to find (f◦f)(x), we need to evaluate f(f(x)).

This means we need to first evaluate f(x), and then evaluate f(f(x)).

To find (f◦f)(81), we need to find f(f(81)).

Using the function f(x), we find f(81):

f(81) = sqrt(81) = 9

Now, we use the function f(x) again to find f(f(81)):

f(f(81)) = f(9)

= sqrt(9)

= 3

Thus, we have found that

(f◦f)(81) = f(f(81))

= 3

Hence, the value of (f0f)(81) is 3.

Therefore, the value of (f0f)(81) is 3.

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the probability as a fraction will be 3/12.

What is a fraction?

If the numerator is bigger, it is referred to as an improper fraction and can also be expressed as a mixed number, which is a whole-number quotient with a proper-fraction remainder.

Any fraction can be expressed in decimal form by dividing it by its denominator. One or more digits may continue to repeat indefinitely or the result may come to a stop at some point.

the letters of the word better appear on a child's blocks, one letter per block. the child arbitrarily selects two of the blocks.

PE followed R When 2blocks selected) - 5 = Bois obtaining R from the remaining 3 people selected 12 men & 10

Hence the probability as a fraction will be 3/12.

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The pairwise comparisons that need to be made for this anova result will be b.3

In order to determine the number of pairwise comparisons needed for a one-way between-subjects ANOVA with three groups, we can use the formula:

N = (k * (k-1)) / 2

Where N represents the number of pairwise comparisons and k represents the number of groups. In this case, k = 3.

Plugging in the values:

N = (3 * (3-1)) / 2

N = (3 * 2) / 2

N = 6 / 2

N = 3

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There are 120 possible ways for two tables and 90 ways for 3 tables.

If we split the six people into 4/1/1, there will be (6 4) ways to select the 4 people sitting together, and 3! ways to arrange them at their table, so this gives (6 4)(3!)=15(6)=90 possibilities.

If we split the six people into 3/2/1, we will get (6 3) ways to select the 3 people sitting together, 2! ways to arrange them at their table, and (3 2) ways to select the 2 people sitting together, so this gives (6 3)⋅2⋅(3 2)=20(2)(3)=120 possibilities.

Finally, there are 120 possible ways for two tables and 90 ways for 3 tables.

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Answer:

7/16

Step-by-step explanation:

unit fractions have 1 as their numerator.

Answer:

\(y = \frac{5}{2} x^{2}\)

Step-by-step explanation:

When you scale a parabola vertically, you multiply the \(x^{2}\) by what you are scaling it vertically by.

For example, say you have  \(y = 8x^{2}\). That means that  \(y = x^{2}\) was scaled vertically by a factor of 8.

I hope this helps!

Answer:

Direct variation

Step-by-step explanation:

Direct variation:y=kx

Inverse variation: y=k*1/x

Answer:

Step-by-step explanation:

To convert the decimal 0.25 to a fraction, we can write it as:

0.25 = 25/100

We can simplify the fraction 25/100 by dividing both the numerator and the denominator by their greatest common factor (GCF), which is 25. This gives us:

25/100 = (25 ÷ 25) / (100 ÷ 25) = 1/4

So the simplified fractional equivalent of the terminating decimal 0.25 is 1/4.

The sampling variance of Spencer's estimator can be calculated using the formula for the variance of the sum or difference of two random variables.

In this case, Spencer's estimator is the average weight of the first and last apple, denoted as (X1 + Xn)/2.

The variance of the sum or difference of two independent random variables is the sum of their individual variances. Since the weights of the apples are independently distributed with mean µ and variance σ^2, the variance of each apple weight is σ^2.

To find the sampling variance of Spencer's estimator, we need to find the variance of (X1 + Xn)/2. Using the formula for variance, we can simplify the calculation as follows:

Var[(X1 + Xn)/2] = (1/4) * Var(X1 + Xn)

Since X1 and Xn are independent, the variance of their sum is the sum of their individual variances:

Var(X1 + Xn) = Var(X1) + Var(Xn) = 2σ^2

Plugging this back into the previous equation, we get:

Var[(X1 + Xn)/2] = (1/4) * 2σ^2 = σ^2/2

Therefore, the sampling variance of Spencer's estimator is σ^2/2.

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Answer:

Step-by-step explanation:

Step one:

given data

Principal = $2500

rate = 1.2%

time = 20 years

Step two:

The simple interest is expressed as

SI= PRT/100

substitute

SI= 2500*1.2*20/100

SI= $600

The account balance after 20 years is

= principal + Simple interest

= 2500+600

= $3100

Jack is picking out some movies to rent, and he is primarily interested in mysteries and foreign films. he has narrowed down his selections to 20 mysteries and 10 foreign films. step 1 of 2: Jack has 27,405 different combinations of 4 movies he can rent from the 20 mysteries and 10 foreign films.

To determine the number of combinations of 4 movies Jack can rent from 20 mysteries and 10 foreign films, you can use the combination formula: C(n, k) = n! / (k!(n-k)!), where n is the total number of options and k is the number of selections.

In this case, there are 30 films in total (20 mysteries + 10 foreign films). So, n = 30, and Jack wants to rent 4 movies, so k = 4. Using the combination formula, C(30, 4) = 30! / (4!(30-4)!) = 30! / (4!26!) = 27,405.

So, there are 27,405 different combinations of 4 movies that Jack can rent from his selection of mysteries and foreign films.

To calculate the number of different combinations of 4 movies that Jack can rent, we need to use the combination formula: nCr = n! / r!(n-r)! where n is the total number of movies (20 mysteries + 10 foreign films = 30), and r is the number of movies Jack wants to rent (4). So the calculation would be: 30C4 = 30! / 4!(30-4)! = 27,405

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Answer:

5y - 2

Step-by-step explanation:

1/3 ( 15y - 6 ) = (15y - 6) / 3 = 5y - 2

Done! Hope you learned how to do this/understood this and have a great day! Please mark me as brainliest, vote 5.0 on my answer and thank me to show some support! Bye!

A curvilinear term in mathematics is "Consisting of, bounded by, or characterized by a curved line." However, the definition of a quadratic is a second-order polynomial equation in a single variable \(0= ax^{2}+bx+c\) with

\(a\neq 0\). A quadratic is a curvilinear term according to my definition, but a function like \($x^{4}$\) would also fit the definition of curvilinear. So, your answer is

False, a quadratic and a curvilinear term are not the same.

False, a curvilinear term is more broad, but quadratics have specific restrictions.

The equation that represents the situation is:

d = 525h

In this equation, d represents the distance traveled and h represents the number of hours spent flying. The equation states that the distance traveled (d) is equal to the product of the speed (525 miles per hour) and the number of hours spent flying (h). This equation shows the relationship between the distance and time for the airplane flying at a constant speed of 525 miles per hour.

       The Equation Representing The Situation is:

       d  =  525 *  h

Make A Plan:

We need to find the Equation representing the relationship between the distance traveled (D) and the number of hours spent flying (H).

The Airplane is flying at a Constant Speed of 525 Miles Per Hour (mph). However, The Distance Traveled is Equal to the speed Multiplied by the Time Spent Flying.  

        d   =   525  *   h

        The Equation Representing The Situation is:

        d  =  525 *  h

I hope this helps you!

Answer:

What is 5% of 45.22?

That would be about 2.3

Now times that by 4 then there is your answer :)

Answer:

x = 8

Step-by-step explanation:

The sum of the measures of two complementary angles is 90°.

m<C + m<D = 90°

5x + 7x - 6 = 90

12x = 96

x = 8

A) The probability that the sample mean is within $500 of the population mean for a sample of size 60 is 0.6611

B) The probability that the sample mean is within $500 of the population mean for a sample of size 120 is 0.7362

The EAI (Error of the Estimate) sampling problem is a specific case of the Central Limit Theorem, which states that the distribution of sample means from a population with a finite variance will be approximately normally distributed as the sample size increases.

The formula for calculating the standard error of the mean is

SE = σ/√n

where SE is the standard error, σ is the population standard deviation, and n is the sample size.

For n = 30, SE = 4,000/√30 = 729.16

A. For a sample size of n = 60, SE = 4,000/√60 = 516.40

To find the probability that the sample mean is within $500 of the population mean, we need to calculate the z-score for a range of +/- $500

z = (x - μ) / SE

where x is the sample mean, μ is the population mean, and SE is the standard error.

For a range of +/- $500, the z-scores are

z = ($51,300 - $51,800) / 516.40 = -0.969

z = ($52,300 - $51,800) / 516.40 = 0.969

Using a standard normal distribution table, the area between z = -0.969 and z = 0.969 is 0.6611.

B. For a sample size of n = 120, SE = 4,000/√120 = 368.93

Following the same steps as above, the z-scores for a range of +/- $500 are

z = ($51,300 - $51,800) / 368.93 = -1.364

z = ($52,300 - $51,800) / 368.93 = 1.364

Using the standard normal distribution table, the area between z = -1.364 and z = 1.364 is 0.7362.

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The total number of rankings is the product of the number of students at each step. Total number of different rankings possible = 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 = 10! ≈ 3.6 × 10^6.

Given that an introductory statistics class has 4 freshmen and 6 sophomores. The students are ranked based on their performance. Therefore, it is required to find the number of different rankings possible. Step 1: Find the total number of students in the class. Total number of students in the class = number of freshmen + number of sophomores = 4 + 6 = 10Step 2: Find the number of ways to select the first-ranked student. There are 10 students to choose from for the first position. Therefore, the number of ways to select the first-ranked student is 10.Step 3: Find the number of ways to select the second-ranked student. There are 9 students remaining after selecting the first-ranked student. Therefore, the number of ways to select the second-ranked student is 9.Step 4: Find the number of ways to select the third-ranked student.There are 8 students remaining after selecting the first two-ranked students.

Therefore, the number of ways to select the third-ranked student is 8.Step 5: Continue the process until all students are ranked. The total number of rankings is the product of the number of students at each step.Total number of different rankings possible = 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 = 10! ≈ 3.6 × 10^6.

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Evaluate the expression is -10.

You must replace each variable with a number and carry out the arithmetic procedures to evaluate an algebraic expression. As 6 + 6 = 12, the variable x in the preceding example is equal to 6. We can replace our variables with their values if we know what they are, then evaluate the expression after doing so.

The division can be done as follows when assessing the phrase 8 4:

−8 ÷ −4 = 2

The expression is thus reduced to:

2 - 12

12 is subtracted from 2 to yield:

-10

Thus, -10 is the correct response.

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Answer:

f(n) = 10 + 3n

Step-by-step explanation:

Each of the expressions has 10 + a certain number of 3's

For example for n = 3 we have
f(3) = 10 + 3 threes = 10 + 3 x 3 = 10 + 9 = 19

For n = 4, we have

f(4) = 10 + 4 threes = 10 + 4 x 3 = 10 + 12 = 22

The others follow the same pattern

So the explicit equation is

f(n) = 10 + 3n

Testing on n = 6 we get

f(6) = 10 + 6n = 10 + 6 x 3 = 10 + 18 = 28

Answer:

10

Step-by-step explanation:

5 - 3 + 8 = 2 + 8 = 10

Have a nice day!