Find the value of the variable(s) in each figure. Explain your reasoning. Thank you in advance

Answer:

Only one solution.

Step-by-step explanation:

y = 3x +2

y -2x =4

y - 2x = 4

=> y = 2x +4

y = 3x + 2

y = 2x + 4

Since both equations are not the same, so the answer cannot be "infinitely many solutions".

They both intersect each other 1 point, so it cannot be "no solutions".

So the answer is "Only 1 solution".

Answer:

x + y = 200

0.08x + 0.24y = 0.18(200)

Step-by-step explanation:

x + y = 200

0.08x + 0.24y = 0.18(200)

The equations which describes the amount of 8% solution used and the amount of 24% solution used are: x+ y=200 and x+3y=450.

An equation is a relationship between two or more variables. They are mostly present in equal to form and are equated to find the value of variables present in them.

let the amount of 8% solution used be x and the amount of 24% solution used be y.

According to question the amount of total solution will be 200ml, So, the equation will be:

x +y=200

Now we have been said that the solution will be 18% saline and 8% saline mixture and 24% saline mixtures are used, So the next equation will be:

0.08x+ 0.24y=0.18*200

8x/100+24/100=18/100*200

8x+24y=3600

8(x+3y)=3600

x+3y=450

Hence the equations which shows the amount of solutions will be x+y=200 and x+3y=450.

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Answer:

1). x = 2.67 units

2). x = 4.80 units

3). x = 6.00 units

Step-by-step explanation:

1). By applying Pythagoras theorem,

 Hypotenuse² = [Leg(1)]² + [leg(2)]²

  12² = x² + b² [Let the base of both the triangles = b units]

  144 = x² + b² ------(1)

  Similarly, 13² = (x + 3)² + b²

  169 = x² + 6x + 9 + b²

  169 - 9 - 6x = x² + b²

  160 - 6x = x² + b² ------(2)

  From equation (1) and (2)

  144 = 160 - 6x

  6x = 160 - 144

  x = [tex]\frac{16}{6}[/tex]

  x = 2.67 units

2). By applying Pythagoras theorem,

  10² = x² + h² [Let the height of the triangle = h]

  100 = x² + h² ------(1)

  13² = (2x)² + h²

  169 = 4x² + h² -----(2)

  By substituting equation (1) from equation (2),

  169 - 100 = (4x² + h²) - (x² + h²)

  69 = 3x²

  x² = 23

  x = √23

  x = 4.795

  x ≈ 4.80 units

3). By applying Pythagoras theorem,

  9² = x² + h² [Let the height of the triangle = h units]

  81 = x² + h² ------(1)

  7² = (x - 4)² + h²

  49 = x² + 16 - 8x + h²

  49 - 16 = x² + h² - 8x

  33 + 8x = x² + h² -------(2)

  From equation (1) and (2)

  81 = 33 + 8x

  8x = 48

   x = 6.00 units

Answer:

a) Pr(drug user| positive test) = 0.3333

b) The probability that he will failed his first test = 0.9703

c) the probability that he is a drug user since  failed his second drug test

= 0.961165

Step-by-step explanation:

From the given information:

Suppose that 1% of the employees of a certain company use illegal drugs.

Probability of illegal drug user = 0.01

Probability of user that do not use drug = 1 - 0.01 = 0.99

From the person that is a illegal drug user, the company performs random drug tests that return positive results = 0.99

Therefore, the negative result for illegal drug user = 1 - 0.99 = 0.01

However, it also has a 2% false positive rate.

i.e the probability of the user that do not use drug has a positive result of 2% = 0.02

Thus, the probability of the user that do not use drug has a negative result of = 1 - 0.02

= 0.98

We are tasked to answer the following questions.

a) Steve, an employee at the company, has a positive test. What is the probability that he is a drug user?

i.e This employee we are taking about is a drug user and he has a positive test.

Thus;

Pr(drug user| positive test) = [tex]\dfrac{0.99 \times 0.01}{0.99 \times 0.01+ 0.02 \times 0.99}[/tex]

Pr(drug user| positive test) = [tex]\dfrac{0.0099}{0.0099+0.0198}[/tex]

Pr(drug user| positive test) = [tex]\dfrac{0.0099}{0.0297}[/tex]

Pr(drug user| positive test) = 0.3333

b) Knowing he failed his first test, what is the probability that Steve will fail his next drug test?

The probability that he will failed his first test = ((0.01 × 0.01) + (0.99×0.98))

The probability that he will failed his first test = ( 1 × 10⁻⁴ + 0.9702)

The probability that he will failed his first test = 0.9703

c)  Steve just failed his second drug test. Now, what is the probability that he is a drug user?

the probability that he is a drug user since he  failed his second drug test using Bayes theorem can be expressed as:

= [tex]\dfrac{0.01 \times(0.99\times 0.99)}{0.01 \times (0.99 \times0.99)+ 0.99(0.02 \times0.02)}[/tex]

the probability that he is a drug user since failed his second drug test

= [tex]\dfrac{0.01 \times(0.9801)}{0.01 \times (0.9801)+ 0.99(4 \times 10^{-4})}[/tex]

the probability that he is a drug user since  failed his second drug test

= [tex]\dfrac{0.009801}{0.009801+ 3.96 \times 10^{-4}}[/tex]

the probability that he is a drug user since  failed his second drug test

= 0.961165

Answer:

The area of larger triangle is 48 ft².

Step-by-step explanation:

Assuming that the area of triangle formula is A = 1/2 × base × height. Then, you have to substitute the following values :

[tex]area = \frac{1}{2} \times b \times h[/tex]

[tex]let \: b = 12,h = 8[/tex]

[tex]area = \frac{1}{2} \times 12 \times 8[/tex]

[tex]area = \frac{1}{2} \times 96[/tex]

[tex]area = 48 \: {feet}^{2} [/tex]

Given that;

A∞bh

A=kbh. where k is a constant

For smaller triangle

A=kbh

16=8(4)k

16=32k

k=½

For bigger triangle

A=kbh

Where k=½ , b= 12 and h=8

A=½(12)8

A=48 square feet

Answer:

16 + 8b ≥ 50

4500

Step-by-step explanation:

He needs at least 50 rooms and has already reserved 16

They are in groups of 8

16 + 8b ≥ 50

Subtract 16 from each side

16+8b-16 ≥ 50 -16

8b≥ 34

Divide by 6

8b/8 ≥ 34/8

b≥ 4.25

We need to round up since we need at least 50

b = 5 since we want the least amount of rooms

Each block is 900

5*900 = 4500 more that he will have to spend

Answer:

0.9259

Step-by-step explanation:

Given the following data :

TOST(x) :4200 3575 3750 3700 4050 2770 4870 4500 3450 2675 3750 3300

RBOT(y) : 370 340 375 310 350 200 400 380 285 220 345 280

The correlation Coefficient tells about the strength of the statistical relationship which exists between two variables. The value of correlation Coefficient ranges from - 1 to +1.

The closer the value of correlation Coefficient is to ±1 , the stronger the correlation Coefficient with a negative and positive values signifying a negative and positive relationship respectively. Value of 1 depicts a perfect correlation while 0 means no relationship exists between them. Values close to zero denotes weak relationship.

Using the online Coefficient of correlation calculator ;

The r value of the data above is 0.9259 which signifies a very strong positive relationship between the variables.

In this exercise we have to calculate the value of the coefficient which can be descriptive statistics as:

0.9259

Given the following data :

[tex]TOST(x) :\\4200\\ 3575\\ 3750 \\3700\\ 4050\\ 2770\\ 4870\\ 4500\\ 3450\\ 2675\\ 3750\\ 3300[/tex][tex]RBOT(y) : \\370 \\340 \\375\\ 310\\ 350\\ 200\\ 400\\ 380\\ 285\\ 220\\ 345\\ 280[/tex]

The correlation Coefficient tells about the strength of the statistical relationship which exists between two variables. The value of correlation Coefficient ranges from - 1 to +1.

The closer the value of correlation Coefficient is to ±1 , the stronger the correlation Coefficient with a negative and positive values signifying a negative and positive relationship respectively. Value of 1 depicts a perfect correlation while 0 means no relationship exists between them. Values close to zero denotes weak relationship.

Using the online Coefficient of correlation calculator, the r value of the data above is 0.9259 which signifies a very strong positive relationship between the variables.

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Answer:

46

Step-by-step explanation:

See attached for reference

The points given:

They form a rectangle as seen in the picture.

We can notice that this is a parallelogram, as respective lines have same difference of coordinates.

So calculating only the two of the sides will be sufficient to get its perimeter:

So, the perimeter:

Answer:

x = 4

Step-by-step explanation:

2( 3x + 3) = 8x - 2

6x + 6 = 8x -2

6x + 8 = 8x

8 = 2x

4 = x

It is given that Y is the midpoint of XZ. If XZ = 8x − 2 and YZ = 3x + 3, So the value of x is x = 4.

Midpoint, as the word suggests, means the point which lies in the middle of something.

Midpoint of a line segment means a point which lies in the mid of the given line segment.

We have been given that Y is the midpoint of XZ. If XZ = 8x − 2 and YZ = 3x + 3, we need to find x.

We know that;

2(YZ) = XZ  

Substitute in the values

2( 3x + 3) = 8x - 2

Use the Distributive Property

6x + 6 = 8x -2

6x + 8 = 8x

8 = 2x

4 = x

Switch the sides to make it easier to read

x = 4

It is given that Y is the midpoint of XZ. If XZ = 8x − 2 and YZ = 3x + 3, So the value of x is x = 4.

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Answer:  C) 50% of the students scored below 70%

Step-by-step explanation:

Mean is the average.  To find the mean (aka average) you add up all of the scores and divide by the number of tests.  

B) The mean can be 70 without any test scoring 70% so B is not true.

A) Since B is not true, then A is not a valid option.

D) We don't know any of the other data so don't know if it is skewed left, skewed right, or normal.  Therefore, option D is not true.

C) If the average is 70%, then half received grades above that score and half received grades below that score.  So, option C is TRUE!

Answer:

A. There is insufficient evidence at the 0.05 level of significance to conclude that Regular and Salt & Vinegar chips have different amounts of chips per bag.

D. Fail to reject H0.

Step-by-step explanation:

From the summary of the given test statistics.

The null and the alternative hypothesis are:

[tex]H_0:\mu_1=\mu_2 \\ \\ Ha:\mu_1 \neq \mu_2[/tex]

This test is also a two tailed test.

Similarly, the t value for the test statistics = 1.44

The p- value - 0.167

The level of significance ∝ = 0.05

The objective we are meant to achieve here is to determine which of the following from the given options are appropriate conclusions for this hypothesis test.

From what we have above:

Decision Rule: We fail to reject the null hypothesis since the p-value is greater than the level of significance at 0.05

CONCLUSION: Therefore, we can conclude that  there is insufficient evidence at the 0.05 level of significance to conclude that Regular and Salt & Vinegar chips have different amounts of chips per bag as we fail to reject H0.

Answer:

Rate per meter=85 Rs. hence , the cost of fencing the square plot at rate of 85 rs. per meter is 937125 Rs.

Complete Question

The  complete question is shown on the first uploaded image

Answer:

  The correct option is C

Step-by-step explanation:

From the question we are told that

      The  number of purple  kernel is  [tex]n_k = 3593[/tex]

        The number of  yellow kernel is  [tex]n_y = 1102[/tex]

Generally the ration of the purple to the yellow kernels is mathematically evaluated as

              [tex]r = \frac{n_k}{n_y}[/tex]

substituting values

              [tex]r = \frac{3593}{1102}[/tex]

              [tex]r = 3.3[/tex]      

              [tex]r \approx 3[/tex]

Therefore the ratio is  

               [tex]1 \ Yellow : 3 \ Purple[/tex]

Answer:

-50

Step-by-step explanation:

Basically get two slopes -50(1)+100 will get you 1,50 (1 is x and 50 is y since its the answer)

-50(0)+100 (0,100)  Y₂-Y₁/X₂-X₁ 50-100/1-0

Rate of change per month = -$50

Answer:

It has been proved that T is compact

Step-by-step explanation:

To prove this using the definition of compactness, let's assume that T is

not compact. Now, if that be the case, an open cover of T will exist. Let's call this open cover "A". Now, this open cover will have no finite subcover.

Now, from the question, since T is closed, it’s complement R\T will be open.

Therefore, if we add the set R\T to the collection of sets A, then we'll have an open cover of R and also of S.

Due to the fact that S is compact, this

cover will have a finite sub - cover which we will call B.

Finally, either B itself or B\{R\T} would be a finite sub - cover of A. This is a contradiction.

Thus, it proves that T has to be compact if S is to be a compact subset of R and T is to be a closed subset of S.

Answer: 250 mi

Step-by-step explanation:

Here we can think in a triangle rectangle:

The distance from Birmingham to Atlanta is roughly 150 mi, and this is one of the cathetus.

And the distance from Birmingham to Nashville is roughly 200 mi, this is the other cathetus of the triangle.

Now, the distance from Atlanta to Nashville will be the hypotenuse of this triangle rectangle.

Now we can apply the Pythagorean's theorem:

A^2 + B^2 = H^2

Where A and B are the cathetus, and H is the hypotenuse:

Then:

H = √(A^2 + B^2)

H = √(150^2 + 200^2) mi = √(62,500) mi = 250 mi

Then the estimated distance from Atlanta to Nashville is 250 mi

Answer:

X ~ Binom (n = 6, p = 0.50)

Step-by-step explanation:

We are given that a box contains 6 cameras and that 3 of them are defective.

A sample of 2 cameras is selected at random.

Let X = Number of defective cameras in the sample.

The above situation can be represented through binomial distribution;

[tex]P(X=r)= \binom{n}{r}\times p^{r} \times (1-p)^{n-r} ;x = 0,1,2,3,......[/tex]

where, n = number of trials (samples) taken = 2 cameras

             x = number of success

            p = probabilitiy of success which in our question is probability that  

                  cameras are defective, i.e. p = [tex]\frac{3}{6}[/tex] = 0.50

So, X ~ Binom (n = 2, p = 0.50)

Now, the binomial probability distribution for X is given by;

[tex]P(X=r)= \binom{6}{r}\times 0.5^{r} \times (1-0.5)^{6-r} ;r = 0,1,2[/tex]

Here, the number of success can be 0, 1, or 2 defective cameras.

Answer:

Step-by-step explanation:

2,444

Answer:

2,444.

Step-by-step explanation:

500+0+12+44+55+500+0+12+44+55+ 500+0+12+44+55+500+0+12+44+55 = 500 + 12 + 44 + 55 + 500 + 12 + 44 + 55 + 500 + 12 + 44 + 55 + 500 + 12 + 44 + 55 = 4(500 + 12 + 44 + 55) = 4(512 + 99) = 4(611) = 2,444.

Hope this helps!

Answer:

7161

Step-by-step explanation:

7 + 7(2) + 7(2)² + ... + 7(2)⁹

= ∑₁¹⁰ 7(2)ⁿ⁻¹

= 7 (1 − 2¹⁰) / (1 − 2)

= 7161

Answer:

  find the difference of points on the graph

Step-by-step explanation:

The cumulative frequency graph (CDF) represents the integral of the probability distribution function (PDF). You find the probability that X is in some interval by subtracting the value of the CDF at the low end of the interval from the CDF value at the high end of the interval.

  p(a < x < b) = cdf(b) -cdf(a)

Answer:

make a table of values

Step-by-step explanation:

then plot using those values

The required graph has been attached which represents the line y = 4/3x

A graph can be defined as a pictorial representation or a diagram that represents data or values.

We have been given the equation of a line below as:

y = 4/3x

Rewrite in slope-intercept form.

y = (4/3)x

Use the slope-intercept form to discover the slope and y-intercept.

Here the slope is 4/3 and  y-intercept = (0, 0)

Any line can be graphed using two points. Select two x values, and plug them into the equation to find the corresponding y values.

When substitute the value of x = 0, then the value of y = 0, and When substitute the value of x = 3, then the value of y = -4,

Hence, the graph represents the line y = 4/3x

Therefore, the required graph of the line y=4/3x will be shown in the as attached file.

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Answer:

Although the question is not clear, It most likely looks like you were asking for the calculation of the savings for the month after increase.

savings for the month after increase = $1172.4

Step-by-step explanation:

First, let us calculate how much was saved before the increase in savings:

monthly income = $19,540

Percentage saved = 4% of monthly income

= 4/100 × 19,540 = 0.04 × 19,540 = $781.6

Next, we are given the ratio of increase in savings as 3:2

Let the new savings amount be x

3 : 2 = x : 781.6

[tex]\frac{3}{2} = \frac{x}{781.6} \\781.6\ \times 3\ =2x\\2344.8 = 2x\\x =\frac{2344.8}{2} \\x = \$1172.4[/tex]

therefore savings for the month after increase = $1172.4

Just incase you were looking for the savings before the increase, the answer is $781.6 (as calculated above)

Answer:

The probability is  [tex]P(X > x ) = 0.19215[/tex]

Step-by-step explanation:

From the question we are told that

   Th The population mean [tex]\mu = \$ 1,999[/tex]

    The  standard deviation is  [tex]\sigma = \$ 574[/tex]

    The  values considered is  [tex]x = \$ 2,500[/tex]

Given that the distribution of the amounts spent follows the normal distribution then the  percent of the adults spend more than $2,550 per year on reading and entertainment is mathematically represented as

    [tex]P(X > x ) = P(\frac{ X - \mu}{\sigma } > \frac{ x - \mu}{\sigma } )[/tex]

Generally  

            [tex]X - \mu}{\sigma } = Z (The \ standardized \ value \ of \ X )[/tex]

So

      [tex]P(X > x ) = P(Z > \frac{ x - \mu}{\sigma } )[/tex]

substituting values

      [tex]P(X > 2500 ) = P(Z > \frac{ 2500 - 1999}{574 } )[/tex]

      [tex]P(X > 2500 ) = P(Z >0.87 )[/tex]

From the normal distribution table the value of [tex]P(Z >0.87 )[/tex] is  

       [tex]P(Z >0.87 ) = 0.19215[/tex]

Thus  

       [tex]P(X > x ) = 0.19215[/tex]

Answer:

Step-by-step explanation:

In order to find B we must first angle C

To find angle C we use the sine rule

That's

[tex] \frac{ |a| }{ \sin(A) } = \frac{ |c| }{ \sin(C) } [/tex]

From the question

a = 15

A = 70°

c = 14

So we have

[tex] \frac{15}{ \sin(70) } = \frac{14}{ \sin(C) } [/tex]

[tex] \sin(C) = \frac{14 \sin(7 0 ) }{15} [/tex]

[tex]C = \sin^{ - 1} ( \frac{14 \sin(70) }{15} ) [/tex]

C = 61.288

Since we've found C we can use it to find B.

Angles in a triangle add up to 180°

To find B add A and C and subtract it from 180°

That's

A + B + C = 180

B = 180 - A - C

B = 180 - 70 - 61.3

To find b we can use the sine rule

That's

[tex] \frac{ |a| }{ \sin(A) } = \frac{ |a| }{ \sin(B) } [/tex]

[tex] \frac{15}{ \sin(70) } = \frac{ |b| }{ \sin(48.7) } [/tex]

[tex] |b| = \frac{15 \sin(48.7) }{ \sin(70) } [/tex]

b = 11.9921

Hope this helps you

Answer:

Option (2)

Step-by-step explanation:

1). If two lines have the same slope, lines are defined as parallel.

m₁ = m₂

2). If the multiplication of the slopes of two lines is (-1), lines will be perpendicular.

m₁ × m₂ = (-1)

Line 1 : It passes through two points (-2, 10) and (1, 1).

Slope of the line 1 = [tex]\frac{y_2-y_1}{x_2-x_1}[/tex]

                              = [tex]\frac{1+2}{10-1}[/tex]

                              = [tex]\frac{3}{9}[/tex]

                         m₁ = [tex]\frac{1}{3}[/tex]

Line 2 : It passes through two points (-2, 8) and (2, -4).

Slope of the line 2 = [tex]\frac{y_2-y_1}{x_2-x_1}[/tex]

                               = [tex]\frac{8+4}{-2-2}[/tex]

                               = [tex]-\frac{12}{4}[/tex]

                         m₂ = -3

Since, m₁ × m₂ = [tex]\frac{1}{3}\times (-3)[/tex]

                        = (-1)

Therefore, given lines are perpendicular to each other.

Option (2) is the correct option.

Answer:

A) t = 1.73

B) p-value =  0.0558

C) Data is not statistically significant because the p-value of 0.0558 is more than the significance value of 0.05

D) The decision means that the design specifications are not met.

E) Type II error

Step-by-step explanation:

The hypotheses are:

H₀: μ = 20

H₁: μ > 20

A) Formula for the test statistic is;

t = (x' - μ)/(s/√n)

Now, we are given;

x' = 21.5

μ = 20

s = 3

n = 12

Thus;

t = (21.5 - 20)/(3/√12)

t = 1.73

B) we have our t-value as 1.73

Now, Degree of freedom(DF) = n - 1

So,DF = 12 - 1 = 11

Using significance level of α = 0.05, t-value = 1.73 and DF = 11, one tailed hypothesis, from online P-value calculator attached, we have;

p-value =  0.0558

C) Data is not statistically significant because the p-value of 0.0558 is more than the significance value of 0.05

D) We will not reject the null hypothesis. The decision means that the design specifications are not met.

E) If the true average activation time of the sprinkler system is, in fact, equal to 20 seconds, then the null hypothesis is false.

Since we did not reject the null hypothesis even though it is false, the error that was committed was therefore a type II error.

Answer:

1 Cruz it makes sense I hope this helps tho

Answer:

Explained below.

Step-by-step explanation:

The ANOVA and Regression output for an application relating maintenance expense (dollars per month) to usage (hours per week) for a particular brand of computer terminal is provided.

(A)

The estimated regression equation equation is:

[tex]y=6.1092+0.8931x[/tex]

Here,

y = maintenance expense (dollars per month)

x = usage (hours per week) for a particular brand of computer terminal

(B)

Consider the Regression output.

The hypothesis to test whether monthly maintenance expense is related to usage is:

H₀: The monthly maintenance expense is not related to usage, i.e. β = 0.

Hₐ: The monthly maintenance expense is related to usage, i.e. β ≠ 0.

Compute the test statistic as follows:

[tex]t=\frac{b}{S.E._{b}}=\frac{0.8931}{0.149}=5.99[/tex]

Compute the p-value as follows:

[tex]p-value=2\times P (t_{8}<5.99}=0.00033[/tex]

The null hypothesis will be rejected if the p-value is less than the significance level.

p-value = 0.00033 < α = 0.05

Reject the null hypothesis.

(C)

Monthly maintenance expense​ is related to usage.

(D)

Yes, the estimated regression equation provide a good fit.

Since the regression coefficient is significant it can be concluded that the regression equation estimated is a good fit.

From the regression output given, the solution to the questions given are outlined thus ;

1.)

Regression equation :

Hence, the estimated regression equation is;

2.)

We can calculate the T-statistic value thus ;

Hence, the T-statistic is given as ;

[tex] T-statistic = \frac{0.8931}{0.149} = 5.99[/tex]

Pvalue (2 tailed) = 0.00033

Decison Region :

Since 0.00033 < 0.05 ; we reject the Null hypothesis.

3.)

Hence, we conclude that monthly expense is related to usage.

4.)

Since, the correlation Coefficient, β ≠ 0 ; Yes, the correlation provides a good fit as it is significant.

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Answer:

Solution ( Second Attachment ) : - 2.017 + 0.656i

Solution ( First Attachment ) : 16.140 - 5.244i

Step-by-step explanation:

Second Attachment : The quotient of the two expressions would be the following,

[tex]6\left[\cos \left(\frac{2\pi }{5}\right)+i\sin \left(\frac{2\pi \:}{5}\right)\right][/tex] ÷ [tex]2\sqrt{2}\left[\cos \left(\frac{-\pi }{2}\right)+i\sin \left(\frac{-\pi \:}{2}\right)\right][/tex]

So if we want to determine this expression in standard complex form, we can first convert it into trigonometric form, then apply trivial identities. Either that, or we can straight away apply the following identities and substitute,

( 1 ) cos(x) = sin(π / 2 - x)

( 2 ) sin(x) = cos(π / 2 - x)

If cos(x) = sin(π / 2 - x), then cos(2π / 5) = sin(π / 2 - 2π / 5) = sin(π / 10). Respectively sin(2π / 5) = cos(π / 2 - 2π / 5) = cos(π / 10). Let's simplify sin(π / 10) and cos(π / 10) with two more identities,

( 1 ) [tex]\cos \left(\frac{x}{2}\right)=\sqrt{\frac{1+\cos \left(x\right)}{2}}[/tex]

( 2 ) [tex]\sin \left(\frac{x}{2}\right)=\sqrt{\frac{1-\cos \left(x\right)}{2}}[/tex]

These two identities makes sin(π / 10) = [tex]\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}[/tex], and cos(π / 10) = [tex]\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}[/tex].

Therefore cos(2π / 5) = [tex]\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}[/tex], and sin(2π / 5) = [tex]\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}[/tex]. Substitute,

[tex]6\left[ \left\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}+i\left\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}\right][/tex] ÷ [tex]2\sqrt{2}\left[\cos \left(\frac{-\pi }{2}\right)+i\sin \left(\frac{-\pi \:}{2}\right)\right][/tex]

Remember that cos(- π / 2) = 0, and sin(- π / 2) = - 1. Substituting those values,

[tex]6\left[ \left\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}+i\left\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}\right][/tex] ÷ [tex]2\sqrt{2}\left[0-i\right][/tex]

And now simplify this expression to receive our answer,

[tex]6\left[ \left\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}+i\left\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}\right][/tex] ÷ [tex]2\sqrt{2}\left[0-i\right][/tex] = [tex]-\frac{3\sqrt{5+\sqrt{5}}}{4}+\frac{3\sqrt{3-\sqrt{5}}}{4}i[/tex],

[tex]-\frac{3\sqrt{5+\sqrt{5}}}{4}[/tex] = [tex]-2.01749\dots[/tex] and [tex]\:\frac{3\sqrt{3-\sqrt{5}}}{4}[/tex] = [tex]0.65552\dots[/tex]

= [tex]-2.01749+0.65552i[/tex]

As you can see our solution is option c. - 2.01749 was rounded to - 2.017, and 0.65552 was rounded to 0.656.

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First Attachment : We know from the previous problem that cos(2π / 5) = [tex]\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}[/tex], sin(2π / 5) = [tex]\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}[/tex], cos(- π / 2) = 0, and sin(- π / 2) = - 1. Substituting we receive a simplified expression,

[tex]6\sqrt{5+\sqrt{5}}-6i\sqrt{3-\sqrt{5}}[/tex]

We know that [tex]6\sqrt{5+\sqrt{5}} = 16.13996\dots[/tex] and [tex]-\:6\sqrt{3-\sqrt{5}} = -5.24419\dots[/tex] . Therefore,

Solution : [tex]16.13996 - 5.24419i[/tex]

Which rounds to about option b.

Answer:

23.6 (approximate value)

Step-by-step explanation:

Answer:

Step-by-step explanation:

23.6