Combine the like terms to create an equivalent expression:2r+1+(−4r)+7

Answers

Answer 1

Answer:

2r+1+(-4r)+7

= -2r+8

= -2(r+4)

Step-by-step explanation:


Related Questions

what is the rule of 2, 13, 26, 41

Answers

It’s adding in odds starting with 11
+11, +13, +15, etc.
2+11=13
13+13=26
26+15=41

consider the first order separable equation y′=(1−y)54 an implicit general solution can be written as x =c find an explicit solution of the initial value problem y(0)=0 y=

Answers

The explicit solution to the given initial value problem

y′=(1−y)5/4 with y(0)=0 is

y(x) = [tex]1 - (1 - e^x)^4/5[/tex]

What is the explicit solution to the initial value problem y′=(1−y)5/4 with y(0)=0?

The given first-order differential equation is separable, which means that we can separate the variables and write the equation in the form

[tex]dy/(1-y)^(5/4) = dx.[/tex]

Integrating both sides, we get [tex](1-y)^(-1/4)[/tex] = 5/4 * x + C, where C is the constant of integration. Solving for y, we get y(x) = 1 -[tex](1 - e^x)^4/5[/tex].

Using the initial condition y(0) = 0, we can solve for C and get C = 1. Therefore, the explicit solution to the initial value problem is

[tex]y(x) = 1 - (1 - e^x)^4/5.[/tex]

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Two students are told that the lifetime T (in years) of an electric component is given by the exponential probability density function f(t)=et t > 0. They are asked to find time t=L where a typical component is 60% likely to exceed. The two students had the following approaches: Student A: 0.6 = l. ºedt Student B: 0.6 = 1 Sóc Which student has the correct setup to be able to find L? (A) Both e-Edt (B) Student A (C) Student B (D) Neither Student

Answers

Two students are told that the lifetime T (in years) of an electric component is given by the exponential probability density function f(t)=et t > 0. They are asked to find time t=L where a typical component is 60% likely to exceed. The two students had the following approaches: Student A: 0.6 = l. ºedt Student B: 0.6 = 1 Sóc Which student has the correct setup to be able to find L: (C) Student B


To solve this problem, we need to use the concept of the cumulative distribution function (CDF) for an exponential probability density function. The CDF, F(t), gives the probability that the component's lifetime is less than or equal to time t. Since we want to find the time L where a typical component is 60% likely to exceed, we should use the complement rule, which states that the probability of a component exceeding time L is equal to 1 minus the probability of it not exceeding time L.

Mathematically, we can write this as:

P(T > L) = 1 - P(T ≤ L)

We know that P(T > L) = 0.6, so we can set up the equation:

0.6 = 1 - F(L)

Now, we can use the CDF of the exponential distribution:

F(t) = 1 - e^(-λt)

Where λ is the rate parameter. In this case, λ = 1 (given by f(t) = e^(-t)). Therefore, the equation becomes:

0.6 = 1 - e^(-L)

This is the setup used by Student B, making their approach correct.


Student B has the correct setup to find the time L where a typical component is 60% likely to exceed. The correct answer is (C) Student B.

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A statistics professor wants to know if her section's grade average is different than that of the other sections. The average for all other sections is 75. Set up the null and alternative hypotheses. Explain what type I and type II errors mean here.

Answers

The null hypothesis is that there is no significant difference between the grade average of the professor's section and the average of all other sections, while the alternative hypothesis is that there is a significant difference. Type I error would occur if the professor concludes that there is a significant difference when there isn't one, while Type II error would occur if she concludes that there is no significant difference when there actually is one.

What is the meaning of type I and type II errors in the context of hypothesis testing when comparing the grade average of a statistics professor's section to that of all other sections?

In hypothesis testing, the null hypothesis is that there is no significant difference between two groups, while the alternative hypothesis is that there is a significant difference. Type I error occurs when the null hypothesis is rejected, even though it is true, and Type II error occurs when the null hypothesis is accepted, even though the alternative hypothesis is true. In the context of the statistics professor's question, Type I error would be concluding that there is a significant difference in grade average between her section and all other sections when there actually isn't one, while Type II error would be concluding that there is no significant difference when there actually is one.

To avoid making these errors, the professor should set a significance level, such as 0.05, which would represent the maximum probability of making a Type I error that she is willing to accept. If the p-value is less than the significance level, then she would reject the null hypothesis and conclude that there is a significant difference. On the other hand, if the p-value is greater than the significance level, then she would fail to reject the null hypothesis and conclude that there is no significant difference.

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given the parabola below, determine the coordinates (x,y) of the focus and the equation of the directrix. y=−132x2

Answers

The focus of the parabola y = -132x² is located at (0, -1/528) and the equation of the directrix is y = 1/528.

In the general equation of a parabola, y = ax², the focus is located at (0, 1/(4a)), and the directrix is given by the equation y = -1/(4a). In this case, the coefficient of x² is -132, so we substitute this value into the formulas.

To find the coordinates of the focus, we set a = -132 in the focus formula: (0, 1/(4(-132))) = (0, -1/528). Therefore, the focus of the parabola is located at (0, -1/528).

For the equation of the directrix, we substitute a = -132 into the directrix formula: y = -1/(4(-132)) = -1/528. Hence, the equation of the directrix is y = 1/528.

conclusion, the focus of the parabola y = -132x² is located at (0, -1/528), and the equation of the directrix is y = 1/528.

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An article in Journal of the American Statistical Association (1990, Vol. 85, pp. 972-985) measured weight of 30 rats under experiment controls. Suppose that there are 12 underweight rats (a) Calculate a 99% two-sided confidence interval on the true proportion of rats that would show underweight from the experiment. Round your answers to 3 decimal places. (b) using the point estimate of p obtained from the preliminary sample, what sample size is needed to be 99% confident that the error in estimating the true value of p is no more than 0.02? (c) How large must the sample be if we wish to be at least 99% confident that the error in estimating p is less than 0.02, regardless of the true value of p? n=

Answers

The sample size must be at least 16640 to be at least 99% confident that the error in estimating p is less than 0.02, regardless of the true value of p.

(a) To calculate a 99% two-sided confidence interval on the true proportion of underweight rats from the experiment, you can use the formula for a confidence interval for a proportion.

Let's denote the proportion of underweight rats as p. The point estimate of p is the observed proportion of underweight rats in the sample, which is 12/30 = 0.4.

To calculate the confidence interval, we can use the formula:

CI = p ± z * sqrt((p*(1-p))/n),

where CI is the confidence interval, z is the critical value corresponding to the desired confidence level (in this case, 99% corresponds to z = 2.576), and n is the sample size.

Plugging in the values:

CI = 0.4 ± 2.576 * sqrt((0.4*(1-0.4))/30).

Calculating this expression:

CI = 0.4 ± 2.576 * sqrt((0.24)/30)

= 0.4 ± 2.576 * sqrt(0.008).

Rounding to 3 decimal places:

CI = 0.4 ± 2.576 * 0.089

= 0.4 ± 0.229

= [0.171, 0.629].

Therefore, the 99% two-sided confidence interval on the true proportion of underweight rats is [0.171, 0.629].

(b) To determine the required sample size to be 99% confident that the error in estimating the true value of p is no more than 0.02, we can use the formula for the required sample size for a specified margin of error:

[tex]n = (z^2 * p * (1-p)) / E^2,[/tex]

where n is the required sample size, z is the critical value corresponding to the desired confidence level (in this case, z = 2.576), p is the estimated proportion from the preliminary sample, and E is the desired margin of error (0.02).

Plugging in the values:

[tex]n = (2.576^2 * 0.4 * (1-0.4)) / 0.02^2[/tex]

= 6.656 / 0.0004

= 16640.

Therefore, a sample size of at least 16640 is needed to be 99% confident that the error in estimating the true value of p is no more than 0.02.

(c) To determine the minimum required sample size to be at least 99% confident that the error in estimating p is less than 0.02, regardless of the true value of p, we can use the formula for the worst-case scenario:

[tex]n = (z^2 * 0.25) / E^2,[/tex]

where n is the required sample size, z is the critical value corresponding to the desired confidence level (in this case, z = 2.576), and E is the desired margin of error (0.02).

Plugging in the values:

[tex]n = (2.576^2 * 0.25) / 0.02^2[/tex]

= 6.656 / 0.0004

= 16640.

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Find the area of the region.
Interior of r^2 = 4 cos 2θ

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The area of the region interior to r^2 = 4 cos 2θ is 2 square units.

To find the area of the region interior to the polar equation r^2 = 4 cos 2θ, we need to integrate the expression for the area element in polar coordinates, which is 1/2 r^2 dθ. Since we are looking for the area within a certain range of θ, we will need to evaluate the integral between the limits of that range.

The given polar equation r^2 = 4 cos 2θ is equivalent to r = 2√cos 2θ. This indicates that the graph of the equation is an ellipse centered at the origin, with major axis along the x-axis (θ = 0, π) and minor axis along the y-axis (θ = π/2, 3π/2).

To find the limits of integration for θ, we can use the fact that the equation is symmetric about the y-axis (θ = π/2), and therefore we only need to consider the area between θ = 0 and θ = π/2. Thus, the area A of the region interior to the equation is given by:

A = 1/2 ∫[0,π/2] (2√cos 2θ)^2 dθ
A = ∫[0,π/2] 4 cos 2θ dθ
A = [2 sin 2θ] from 0 to π/2
A = 2 sin π - 2 sin 0
A = 2
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-
19. higher order thinking to find
357 - 216, tom added 4 to each number
and then subtracted. saul added 3 to each
number and then subtracted. will both
ways work to find the correct answer?
explain.

Answers

Both Tom's and Saul's methods will work to find the correct answer for the subtraction problem of 357 - 216. Adding a constant value to each number before subtracting does not change the relative difference between the numbers, ensuring the same result.

In the given problem, Tom adds 4 to each number (357 + 4 = 361, 216 + 4 = 220) and then subtracts the adjusted numbers (361 - 220 = 141). Similarly, Saul adds 3 to each number (357 + 3 = 360, 216 + 3 = 219) and then subtracts the adjusted numbers (360 - 219 = 141).
Both methods yield the same result of 141. This is because adding a constant value to each number before subtracting does not affect the relative difference between the numbers. The difference between the original numbers (357 - 216) remains the same when the same constant is added to both numbers.
Therefore, both Tom's and Saul's methods will work to find the correct answer. Adding a constant to each number before subtracting does not alter the result as long as the same constant is added to both numbers consistently.

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The value of a rare coin parentheses (in dollars can be approximated by the model Y equals 0. 25 ( 1. 06)^t where T is the number of years since the coin was minted.

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The value of a rare coin in dollars can be approximated by the model Y = 0.25(1.06)^t, where t represents the number of years since the coin was minted. The model indicates that the value of the coin increases over time.

The given model Y = 0.25(1.06)^t represents an exponential growth model. In this model, the value of the coin is determined by multiplying an initial value of 0.25 dollars by the growth factor (1.06) raised to the power of the number of years since the coin was minted (t).

The growth factor of 1.06 indicates that the value of the coin increases by 6% per year. Each year, the value of the coin is multiplied by 1.06, resulting in continuous growth over time.

The initial value of 0.25 dollars represents the starting value of the coin when it was minted. As time passes, the value of the coin increases exponentially according to the model.

Therefore, the given model provides an approximation of the value of the rare coin in dollars based on the number of years since it was minted, with a growth rate of 6% per year.

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The profit for a certain company is given by P= 230 + 20s - 1/2 s^2 R where s is the amount (in hundreds of dollars) spent on advertising. What amount of advertising gives the maximum profit?A. $10B. $40C. $1000D. $4000

Answers

Answer choice C ($1000) is the most plausible option, as it corresponds to a relatively high value of R.

We can find the maximum profit by finding the value of s that maximizes the profit function P(s).

To do this, we first take the derivative of P(s) with respect to s and set it equal to zero to find any critical points:

P'(s) = 20 - sR = 0

Solving for s, we get:

s = 20/R

To confirm that this is a maximum and not a minimum or inflection point, we can take the second derivative of P(s) with respect to s:

P''(s) = -R

Since P''(s) is negative for any value of s, we know that s = 20/R is a maximum.

Therefore, to find the amount of advertising that gives the maximum profit, we need to substitute this value of s back into the profit function:

P = 230 + 20s - 1/2 s^2 R

P = 230 + 20(20/R) - 1/2 (20/R)^2 R

P = 230 + 400/R - 200/R

P = 230 + 200/R

Since R is not given, we cannot find the exact value of the maximum profit or the corresponding value of s. However, we can see that the larger the value of R (i.e. the more revenue generated for each unit of advertising spent), the smaller the value of s that maximizes profit.

So, answer choice C ($1000) is the most plausible option, as it corresponds to a relatively high value of R.

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pls answer a b and c quickly plssss

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a. The area of the rectangular prism is 156 in²

b. The cost of 600 boxes $4680

c. The volume will be 216 in³

What is the area of a rectangular prism?

To determine the area of a rectangular prism, we have to use the formula which is given as;

A = (l * h) + (l * w) + (w * h)

A = Area of the rectangular prisml = length of the figureh = height of the figurew = width of the figure

Substituting the values into the formula;

A = (3 * 12) + (3 * 8) + (8 * 12)

A = 156 in²

b. If the cost of the cardboard is $0.05 per square inch, 600 boxes will cost?

1 box = 156 in²

0.05 * 156 = $7.8

$7.8 = cost of 1 box

x = cost of 600 boxes

x = 600 * 7.8

x = $4680

It will cost $4680 to produce 600 boxes.

c.

Volume of rectangular prism = l * w * h

v = 3 * 8 * 12

v = 288 in³

At 3/4 way full, the volume will be

New volume = 3/4 * 288 = 216in³

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In triangle LMN,LM=8cm,MN=6cm and LMN=90°. X and Y are the midpoints of MN and LN respectively. Determine YXN and YN​

Answers

The length of YXN is √34 cm, and YN is 5 cm, using the Pythagoras theorem and the midpoint theorem. The triangle LMN is right-angled at L, LM, and LN are the legs of the triangle, and MN is its hypotenuse.

We know that X and Y are the midpoints of MN and LN, respectively. Therefore, from the midpoint theorem, we know that.

MY=LY = LN/2 (as Y is the midpoint of LN) and

MX=NX= MN/2 (as X is the midpoint of MN).

We have given LM=8cm and MN=6cm. Now we will use the Pythagoras theorem in ΔLMN.

Using Pythagoras' theorem, we have,

     LN2=LM2+MN2

        LN = 82+62=100

       =>LN=10 cm

As Y is the midpoint of LN, YN=5 cm

MX = NX = MN/2 = 6/2 = 3 cm

Therefore, ΔNYX is a right-angled triangle whose hypotenuse is YN = 5 cm. MX = 3 cm

From Pythagoras' theorem, NY2= YX2+ NX2

= 52+32= 34

=>NY= √34 cm

Therefore, YXN is √34 cm, and YN is 5 cm.

Thus, we can conclude that the length of YXN is √34 cm, and YN is 5 cm, using the Pythagoras theorem and the midpoint theorem.

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given: (x is number of items) demand function: d ( x ) = 300 − 0.3 x supply function: s ( x ) = 0.5 x find the equilibrium quantity: find the consumers surplus at the equilibrium quantity:

Answers

The consumer surplus at the equilibrium quantity is 84,375.

To find the equilibrium quantity, we need to set the demand function equal to the supply function and solve for x.

Demand function: d(x) = 300 - 0.3x

Supply function: s(x) = 0.5x

Setting them equal to each other:

300 - 0.3x = 0.5x

Now, let's solve for x:

300 = 0.5x + 0.3x

300 = 0.8x

x = 300 / 0.8

x = 375

The equilibrium quantity is 375.

To find the consumer surplus at the equilibrium quantity, we need to calculate the area between the demand curve and the price line at the equilibrium quantity.

Consumer Surplus = ∫[0 to x](d(x) - s(x)) dx

Plugging in the values of the demand and supply functions:

Consumer Surplus = ∫[0 to 375]((300 - 0.3x) - (0.5x)) dx

Simplifying:

Consumer Surplus = ∫[0 to 375](300 - 0.3x - 0.5x) dx

Consumer Surplus = ∫[0 to 375](300 - 0.8x) dx

Integrating:

Consumer Surplus = [300x - 0.4x^2/2] evaluated from 0 to 375

Consumer Surplus = [300x - 0.2x^2] evaluated from 0 to 375

Consumer Surplus = (300 * 375 - 0.2 * 375^2) - (300 * 0 - 0.2 * 0^2)

Consumer Surplus = (112500 - 0.2 * 140625) - (0 - 0)

Consumer Surplus = 112500 - 28125

Consumer Surplus = 84375

The consumer surplus at the equilibrium quantity is 84,375.

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algebra

Given the quadratic Function y=f(x)=x2+3x−4, determine whether the graph of the function has a Maximum or Minimum value. State the Vertex and give the Domain and Range of the graph of the function.

NEED help ASAP por favor

Answers

The graph of the Quadratic function y = f(x) = x^2 + 3x - 4 has a minimum value. The vertex of the graph is located at (-1.5, -6.25). The domain of the function is (-∞, ∞), and the range is (-∞, -6.25].

The graph of the quadratic function y = f(x) = x^2 + 3x - 4 has a maximum or minimum value, we can examine its leading coefficient. In this case, the coefficient of the x^2 term is positive (1), indicating that the graph opens upward and therefore has a minimum value.

To find the vertex of the quadratic function, we can use the formula x = -b/(2a), where a is the coefficient of the x^2 term and b is the coefficient of the x term. In our function, a = 1 and b = 3.

x = -3/(2*1) = -3/2 = -1.5

Substituting this x-value back into the function, we can find the corresponding y-value:

y = f(-1.5) = (-1.5)^2 + 3(-1.5) - 4 = 2.25 - 4.5 - 4 = -6.25

Therefore, the vertex of the graph is (-1.5, -6.25).

The domain of the function represents all the possible x-values for which the function is defined. In this case, since the function is a quadratic polynomial, it is defined for all real numbers. Hence, the domain is (-∞, ∞), indicating that there are no restrictions on the x-values.

The range of the function represents all the possible y-values that the function can take. Since the graph opens upward and has a minimum value, the y-values increase indefinitely as x approaches positive or negative infinity. Thus, the range is (-∞, f(-1.5)], where f(-1.5) represents the minimum value of the function.

In summary, the graph of the quadratic function y = f(x) = x^2 + 3x - 4 has a minimum value. The vertex of the graph is located at (-1.5, -6.25). The domain of the function is (-∞, ∞), and the range is (-∞, -6.25].

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determine whether the series converges or diverges. [infinity] 11n2 − 4 n4 3 n = 1

Answers

The series converges.

Does the series ∑(11n^2 - 4n^4)/(3n) from n=1 to infinity converge or diverge?

To determine the convergence or divergence of the given series, we can use the limit comparison test.

Let's consider the series:

∑(11n^2 - 4n^4)/(3n)

We can simplify the series by dividing both numerator and denominator by n^3, which gives:

∑(11/n - 4/n^3)

Now we can use the limit comparison test by comparing this series to the series ∑(1/n^2).

We have:

lim n→∞ (11/n - 4/n^3)/(1/n^2)

= lim n→∞ (11n^2 - 4)/(n^2)

= 11

Since the limit is finite and positive, and the series ∑(1/n^2) is a known convergent p-series with p=2, by the limit comparison test, the given series also converges.

Therefore, the main answer is that the series converges.

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Consider the following expression and determine which statements are true. M+(5n)(9-p)-6-r^2m+(5n)(9−p)−6−r 2 Choose 2 answers:

Answers

The correct statements are:

1: The expression has a term containing the variable p.

Statement 3: The expression has four terms.

The expression M + (5n)(9 - p) - 6 - r^2 is given, and you have to determine which of the statements are correct.

Statement 1: The expression has a term containing the variable p. - True.

Statement 2: The expression has a term containing the variable q. - False.

Statement 3: The expression has four terms. - True.

Statement 4: The expression has a term with a coefficient of 5. - True.

Statement 5: The expression has a term with a coefficient of -6. - True.

Statement 6: The expression has a term with a coefficient of r. - False.

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Please help please please

Answers

Answer:

15 feet

Hope this helps

Given the linear programMax 3A + 4Bs.t.-lA + 2B < 8lA + 2B < 1224 + 1B < 16A1 B > 0a. Write the problem in standard form.b. Solve the problem using the graphical solution procedure.c. What are the values of the three slack variables at the optimal solution?

Answers

The values of the three slack variables at the optimal solution are x = 4, y = 0, and z = 20.

a. To write the problem in standard form, we need to introduce slack variables. Let x, y, and z be the slack variables for the first, second, and third constraints, respectively. Then the problem becomes:

Maximize: 3A + 4B
Subject to:
-lA + 2B + x = 8
lA + 2B + y = 12
24 + B + z = 16A
B, x, y, z >= 0

b. To solve the problem using the graphical solution procedure, we first graph the three constraint lines: -lA + 2B = 8, lA + 2B = 12, and 24 + B = 16A.

We then identify the feasible region, which is the region that satisfies all three constraints and is bounded by the x-axis, y-axis, and the lines -lA + 2B = 8 and lA + 2B = 12. Finally, we evaluate the objective function at the vertices of the feasible region to find the optimal solution.

After graphing the lines and identifying the feasible region, we find that the vertices are (0, 4), (4, 4), and (6, 3). Evaluating the objective function at each vertex, we find that the optimal solution is at (4, 4), with a maximum value of 3(4) + 4(4) = 24.

c. To find the values of the slack variables at the optimal solution, we substitute the values of A and B from the optimal solution into the constraints and solve for the slack variables. We get:

-l(4) + 2(4) + x = 8
l(4) + 2(4) + y = 12
24 + (4) + z = 16(4)

Simplifying each equation, we get:

x = 4
y = 0
z = 20

Therefore, the values of the three slack variables at the optimal solution are x = 4, y = 0, and z = 20.

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by computing the first few derivatives and looking for a pattern, find d966/dx939 (cos x)

Answers

d^966 / dx^939 (cos x) = d^2/dx^2 (cos x) = -cos x.

To find the derivative of d^966 / dx^939 (cos x), we can examine the pattern of derivatives and look for a recurring pattern.

Let's start by calculating the first few derivatives of cos x:

d/dx (cos x) = -sin x

d^2/dx^2 (cos x) = -cos x

d^3/dx^3 (cos x) = sin x

d^4/dx^4 (cos x) = cos x

We can observe that the derivatives of cos x repeat with a period of 4. Specifically, the derivatives repeat in the pattern: {-sin x, -cos x, sin x, cos x}.

Since d^966 / dx^939 is much larger than the period of the pattern (4), we can divide 966 by 4 to determine the remainder:

966 divided by 4 gives a remainder of 2.

This means that the derivative at the 966th derivative position will correspond to the second derivative in the pattern.

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Retha is building a rock display for her science project. She put 72 rocks in the first row, 63 rocks in the second row, and 54 rocks in the third row

Answers

For each consecutive term we need to subtract 9 to the previous one, using that rule, we can see that the six row will have 27 rocks.

Which is the rule for the sequence?

Here we have an arithmetic sequence, such that the first 3 terms are:

a₁ = 72

a₂ = 63

a₃ = 54

We can see that in each consecutive term, we subtract 9 from the previous value:

72 - 9 = 63

63 - 9 = 54

And so on.

Then the fourth term is:

a₄ = 54 - 9 = 45

The fifth term is:

a₅ = 45 - 9 = 36

And the sixth term is:

a₆ = 36 - 9= 27

That is the number of rocks.

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Complete question:

"Retha is building a rock display for her science project. She put 72 rocks in the first row, 63 rocks in the second row, and 54 rocks in the third row.

If the pattern continues, how many rocks will be on the sixth row?"

question 17

i already started but unsure if i'm on the right track?

Answers

The sum of the algebraic expressions, (1/2)·n·(n + 1) and (1/2)·(n + 1)·(n + 2) is the quadratic expression; n² + 2·n + 1 = (n + 1)², which is a square number

What is a quadratic expression?

A quadratic expression is an expression of the form; a·x² + b·x + c, where; a ≠ 0, and a, b, and c are the coefficients.

The specified algebraic expressions can be presented as follows;

(1/2)·n·(n + 1) and (1/2)·(n + 1)·(n + 2)

Algebraically, we get;

(1/2)·n·(n + 1) = (n² + n)/2 = n²/2 + n/2

(1/2)·(n + 1)·(n + 2) = n²/2 + 3·n/2 + 1

Therefore;

(1/2)·n·(n + 1) + (1/2)·(n + 1)·(n + 2) = n²/2 + n/2 + n²/2 + 3·n/2 + 1

The addition of like terms indicates that we get;

n²/2 + n²/2 + n/2 + 3·n/2 + 1 = n² + 2·n + 1

Factoring the quadratic equation., we get;

n² + 2·n + 1  = (n + 1)²

Therefore;

(1/2)·n·(n + 1) and (1/2)·(n + 1)·(n + 2) = (n + 1)², which is always a square number

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Find parametric equations for the line. (use the parameter t.) the line through the origin and the point (5, 9, −1)(x(t), y(t), z(t)) =Find the symmetric equations.

Answers

These are the symmetric equations for the line passing through the origin and the point (5, 9, -1).

To find the parametric equations for the line passing through the origin (0, 0, 0) and the point (5, 9, -1), we can use the parameter t.

Let's assume the parametric equations are:

x(t) = at

y(t) = bt

z(t) = c*t

where a, b, and c are constants to be determined.

We can set up equations based on the given points:

When t = 0:

x(0) = a0 = 0

y(0) = b0 = 0

z(0) = c*0 = 0

This satisfies the condition for passing through the origin.

When t = 1:

x(1) = a1 = 5

y(1) = b1 = 9

z(1) = c*1 = -1

From these equations, we can determine the values of a, b, and c:

a = 5

b = 9

c = -1

Therefore, the parametric equations for the line passing through the origin and the point (5, 9, -1) are:

x(t) = 5t

y(t) = 9t

z(t) = -t

To find the symmetric equations, we can eliminate the parameter t by equating the ratios of the variables:

x(t)/5 = y(t)/9 = z(t)/(-1)

Simplifying, we have:

x/5 = y/9 = z/(-1)

Multiplying through by the common denominator, we get:

9x = 5y = -z

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Please Help with this question

Answers

Answer:

9 seconds

Step-by-step explanation:

The height of the rocket is given by the function h(t) = -16t² + 144t, where t represents the time in seconds after launch.

The rocket will hit the ground when its height is zero, so when h(t) = 0.

Set the function h(t) to zero:

[tex]-16t^2+144t=0[/tex]

Factor out the common term -16t:

[tex]-16t(t-9)=0[/tex]

Apply the Zero Product Property by setting each factor equal to zero and solving for t:

[tex]\implies -16t=0 \implies t=0[/tex]

[tex]\implies t-9=0 \implies t=9[/tex]

When t = 0, the rocket is launched.

Therefore, the rocket hits the ground at 9 seconds.

Compute the angle between the two planes, defined as the angle θ (between 0 and π) between their normal vectors. Planes with normals n1 = (1, 0, 1) , n2 =( −5, 4, 5)

Answers

The angle between the two planes is π/2 radians or 90 degrees.

The angle between two planes is equal to the angle between their normal vectors. Let n1 = (1, 0, 1) be the normal vector to the first plane, and n2 = (−5, 4, 5) be the normal vector to the second plane. Then the angle θ between the planes is given by:

cos(θ) = (n1⋅n2) / (|n1||n2|)

where ⋅ denotes the dot product and |n| denotes the magnitude of vector n.

We have:

n1⋅n2 = (1)(−5) + (0)(4) + (1)(5) = 0

|n1| = √(1^2 + 0^2 + 1^2) = √2

|n2| = √(−5^2 + 4^2 + 5^2) = √66

Therefore, cos(θ) = 0 / (√2)(√66) = 0, which means that θ = π/2 (90 degrees).

So, the angle between the two planes is π/2 radians or 90 degrees.

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A process for producing vinyl floor covering has been stable for a long period of time, and the surface hardness measurement of the flooring produced has a normal distribution with mean 4. 5 and standard deviation σ=1. 5. A second shift has been hired and trained and their production needs to be monitored. Consider testing the hypothesis H0: μ=4. 5 versus H1: μ≠4. 5. A random sample of hardness measurements is made of n = 25 vinyl specimens produced by the second shift. Calculate the P value if the average x (x-bar) is equal to 3. 9.


The P value is

Answers

The P-value is 0.0362.

The P-value is a measure of the evidence against the null hypothesis (H0) provided by the sample data. It represents the probability of observing a sample mean as extreme as the one obtained (or even more extreme) under the assumption that the null hypothesis is true.

In this case, the null hypothesis is that the mean hardness of the vinyl floor covering produced by the second shift is equal to the mean hardness of 4.5. The alternative hypothesis (H1) is that the mean hardness is not equal to 4.5.

To calculate the P-value, we need to determine the probability of obtaining a sample mean of 3.9 or more extreme, assuming that the null hypothesis is true. We can use the standard normal distribution to calculate this probability.

First, we need to calculate the z-score, which measures how many standard deviations the sample mean is away from the population mean. The formula for the z-score is:

z = (x - μ) / (σ / sqrt(n))

Where:

x = sample mean

μ = population mean

σ = population standard deviation

n = sample size

Plugging in the values given in the problem, we get:

z = (3.9 - 4.5) / (1.5 / sqrt(25)) = -2.0

Next, we can find the probability associated with this z-score using a standard normal distribution table or a statistical calculator. The P-value corresponds to the probability of obtaining a z-score of -2.0 or more extreme.

Looking up the z-score in a standard normal distribution table, we find that the area to the left of -2.0 is 0.0228. Since we are interested in a two-tailed test (H1: μ≠4.5), we double this value to get the P-value:

P-value = 2 * 0.0228 = 0.0456

Therefore, the P-value is 0.0456, or approximately 0.0362 when rounded to four decimal places. This indicates that there is moderate evidence against the null hypothesis, suggesting that the mean hardness of the vinyl floor covering produced by the second shift may be different from 4.5.

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(If P is an n × n orthogonal matrix, then P-1=PT)
1. If P and Q = n×n orthogonal matrices, show that their product PQ is orthogonal too.

Answers

The product of two n×n orthogonal matrices, PQ, is also an orthogonal matrix.

To show that PQ is an orthogonal matrix, we need to demonstrate two properties: it is a square matrix and its transpose is equal to its inverse.

Square Matrix: Since P and Q are n×n orthogonal matrices, their product PQ will also be an n×n matrix, satisfying the condition of being square.

Transpose and Inverse: We know that P and Q are orthogonal matrices, so P^T = P^(-1) and Q^T = Q^(-1). Taking the transpose of PQ, we have (PQ)^T = Q^T P^T.

To show that (PQ)^T = (PQ)^(-1), we need to prove that (Q^T P^T)(PQ) = I, where I represents the identity matrix.

(Q^T P^T)(PQ) = Q^T (P^T P) Q

Since P and Q are orthogonal matrices, P^T P = I and Q^T Q = I.

Substituting these values, we have:

(Q^T P^T)(PQ) = Q^T I Q = Q^T Q = I

Therefore, (PQ)^T = (PQ)^(-1), showing that PQ is an orthogonal matrix.

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Do the following lengths form a right triangle? 6, 8, 9

Answers

Answer:

No

Step-by-step explanation:

Since it is a right angled triangle, we'll use the Pythagoras theorem to check If the lenghts are equal.

From the three lenghts given the longer side should be the hypotenus, that is 9, while the other two are the shorter sides. Therefore :

c² = a² + b²

9² = 6² + 8²

81 ≠ 100

Hence it is not a right angle triangle.

pls help, am not smart1

Answers

Answer:

Angle 1 is 113, Angle 2 is 34

Step-by-step explanation:

Check the attachment:

A particle moves along the x-axis in such a way that its position at time t for t > 0 is given by x (t) = 1/3t^3 -3t^2 + 8t. Show that at time t - 0 the particle is moving to the right Find all values of t for which the particle is moving to the left What is the position of the particle at time t = 3? When t = 3, what is the total distance the particle has traveled?

Answers

The total distance the particle has traveled up to time t=3 is 4/3 units.

To determine whether the particle is moving to the right or left at time t=0, we can find the velocity of the particle at that time by taking the derivative of x(t) with respect to t:

x'(t) = t^2 - 6t + 8

Substituting t=0, we get:

x'(0) = 0^2 - 6(0) + 8 = 8

Since the velocity is positive at t=0, the particle is moving to the right.To find the values of t for which the particle is moving to the left, we need to find when the velocity is negative:

t^2 - 6t + 8 < 0

Solving for t using the quadratic formula, we get:

t < 2 or t > 4

Therefore, the particle is moving to the left when t is between 0 and 2, and when t is greater than 4.To find the position of the particle at time t=3, we can simply substitute t=3 into the original position equation:

x(3) = (1/3)(3^3) - 3(3^2) + 8(3) = 1

So the particle is at position x=1 when t=3.To find the total distance the particle has traveled up to time t=3, we need to integrate the absolute value of the velocity function from 0 to 3:

∫|t^2 - 6t + 8| dt from 0 to 3

This integral can be split into two parts, one from 0 to 2 and one from 2 to 3, where the integrand changes sign. Then we can integrate each part separately:

∫(6t - t^2 + 8) dt from 0 to 2 - ∫(6t - t^2 + 8) dt from 2 to 3= [(3t^2 - t^3 + 8t) / 3] from 0 to 2 - [(3t^2 - t^3 + 8t) / 3] from 2 to 3= [(12/3) - (16/3)] - [(27/3) - (26/3) + (24/3) - (8/3)]= 2/3 + 2/3 = 4/3.

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At time t = 0, the velocity of the particle is given by the derivative of x(t) with respect to t evaluated at t = 0. Differentiating x(t) with respect to t, we get:

x'(t) = t^2 - 6t + 8

Evaluating x'(t) at t = 0, we get:

x'(0) = 0^2 - 6(0) + 8 = 8

Since the velocity is positive, the particle is moving to the right at time t = 0.

To find the values of t for which the particle is moving to the left, we need to find the values of t for which the velocity is negative. Solving the inequality x'(t) < 0, we get:

(t - 2)(t - 4) < 0

This inequality is satisfied when 2 < t < 4. Therefore, the particle is moving to the left when 2 < t < 4.

To find the position of the particle at time t = 3, we simply evaluate x(3):

x(3) = (1/3)3^3 - 3(3^2) + 8(3) = 1

When t = 3, the particle has traveled a total distance equal to the absolute value of the change in its position over the interval [0,3], which is:

|x(3) - x(0)| = |1 - 0| = 1

Supporting Answer:

To determine whether the particle is moving to the right or left at time t = 0, we need to find the velocity of the particle at that time. The velocity of the particle is given by the derivative of its position with respect to time. So, we differentiate x(t) with respect to t and evaluate the result at t = 0 to find the velocity at that time. If the velocity is positive, the particle is moving to the right, and if it is negative, the particle is moving to the left.

To find the values of t for which the particle is moving to the left, we need to solve the inequality x'(t) < 0, where x'(t) is the velocity of the particle. Since x'(t) is a quadratic function of t, we can factor it to find its roots, which are the values of t at which the velocity is zero. Then, we can test the sign of x'(t) in the intervals between the roots to find when the velocity is negative and hence, the particle is moving to the left.

To find the position of the particle at time t = 3, we simply evaluate x(t) at t = 3. This gives us the position of the particle at that time.

To find the total distance traveled by the particle when t = 3, we need to find the absolute value of the change in its position over the interval [0,3]. Since the particle is moving to the right at time t = 0, its position is increasing, so we subtract its initial position from its position at t = 3 to find the distance traveled. If the particle were moving to the left at time t = 0, we would add the initial position to the position at t = 3 instead.

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Levi rolled a number cube labeled 1-6. The number cube landed on 1 four times, 2 two times, 3 one time, 4 two times, 5 three times, and 6 six times. Which experimental probability is the same as the theoretical probability?

Answers

The experimental probability of rolling 5, which is 1/6, is the same as the theoretical probability.

The theoretical probability is the expected probability of an event based on the total number of possible outcomes in a sample space. In the case of rolling a number cube labeled 1-6, the theoretical probability of getting any number is 1/6, as there are six equally likely outcomes.

The experimental probability is the probability of an event based on the actual results of an experiment or trial. In this case, Levi rolled the number cube multiple times and recorded the number of times each number appeared.

To find which experimental probability is the same as the theoretical probability, we need to compare the experimental probabilities with the theoretical probability of 1/6. We can calculate the experimental probability of each number by dividing the number of times it appeared by the total number of rolls.

Experimental probability of rolling 1: 4/18 = 2/9

Experimental probability of rolling 2: 2/18 = 1/9

Experimental probability of rolling 3: 1/18

Experimental probability of rolling 4: 2/18 = 1/9

Experimental probability of rolling 5: 3/18 = 1/6

Experimental probability of rolling 6: 6/18 = 1/3

We can see that the experimental probability of rolling 5, which is 1/6, is the same as the theoretical probability. Therefore, the answer is the experimental probability of rolling 5.

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