Answer:
-6i
Step-by-step explanation:
Complex roots have to come in conjugate pairs
So if we have 6i as a root, we must have -6i as a root
Answer:
-6i
Step-by-step explanation:
Hello, because this polynomial function has real coefficients and 6i is a zero, the conjugate of 6i is a zero as well. It means -6i is a zero.
The degree is 4 the number of zeroes is less or equal to 4 and we have already, 6, 4, 6i and -6i. So we have all the zeroes.
Thank you
What is the value of (–7 + 3i) + (2 – 6i)?
a. –9 – 3i
b. –9 + 9i
c. –5 + 9i
d. –5 – 3i
Answer:
d
Step-by-step explanation:
(-7 + 3i) + (2-6i)
=-7 + 3i + 2 -6i
=(-7+2) + (3i -6i)
=-5 -3i
Answer:
(-7+3I)+(2-6I)
= -7+3i+2-6i
= -5-3I
so answer is d ie -5-3i
Consider the following binomial experiment: A study in a certain community showed that 6% of the people suffer from insomnia. If there are 10,300 people in this community, what is the standard deviation of the number of people who suffer from insomnia?
Answer:
The standard deviation is [tex]\sigma = 24.10[/tex]
Step-by-step explanation:
From the question we are told that
The proportion of those that suffer from insomnia is p = 6% = 0.06
The sample size is n = 10300
Generally the proportion of those that do not suffer from insomnia is mathematically represented as
[tex]q = 1-p[/tex]
substituting values
[tex]q = 1 -0.06[/tex]
[tex]q = 0.94[/tex]
Generally the standard deviation is mathematically evaluated as
[tex]\sigma = \sqrt{n * p * q }[/tex]
substituting values
[tex]\sigma = \sqrt{ 10300 * 0.06 * 0.94 }[/tex]
[tex]\sigma = 24.10[/tex]
Using the binomial probability concept, the standard deviation of the number of people who suffer from insomnia is 24.10
Recall :
[tex] standard \: deviation, σ = \sqrt{n \times \: p \: (1 - p)} [/tex] p = probability of success = 6% = 0.061 - p = 1 - 0.06 = 0.94Sample size, n = 10300Substituting the values into the equation :
[tex] standard \: deviation, σ = \sqrt{10300 \times \: 0.06 \: (1 - 0.06)} [/tex]
[tex] standard \: deviation, σ = \sqrt{10300 \times \: 0.06 \: 0.94} [/tex]
[tex] standard \: deviation, σ = \sqrt{580.92} = 24.10[/tex]
Hence, the standard deviation is 24.10.
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I have a circle that has a radius of 8 in. What is the circumference of the circle? What is the area of the circle? ( use 3.14 for pi).Explain your steps. Please Give A clear explanation The best answer gets brainliest.
Answer:
The circumference is 50.24 in. and the area is 200.96 in².
Step-by-step explanation:
The circumference formula is C = 2πr where C = Circumference, π = pi and r = radius. We know that r = 8 and π = 3.14 and that we're solving for C, so we can substitute those values into the equation to get C = 2 * 3.14 * 8 = 50.24 in.
The area formula is A = πr² where A = Area, π = pi and r = radius. Again, we're solving for A and we know that r = 8 and π = 3.14 so A = 3.14 * 8² = 3.14 * 64 = 200.96 in².
Answer:
The circumference is 50.24 in. and the area is 200.96 in².
Step-by-step explanation:
MARK SNOG AS BRAINLIEST
Type the correct answer in each box. Use numerals instead of words,
The domain of this function is {-12, -6, 3, 15).
y = -32 +7
Complete the table based on the given domain.
y
6
0
5
15
15
Reset
Next
Answer:
x = -6,3,15,-12; y = 11,5,-3,15
Step-by-step explanation:
Domain is the x value, so plugged in the x values into the equation and got the y values or range.
Answer:
x: y:
-6 11
3 5
15 -3
-12 15
what are the steps required to determine the equation of a quadratic function given its zeros and a point?
Answer:
Below
Step-by-step explanation:
The quadratic equations form is:
● ax^2+bx+c
Using the zeroes, we can write a factored form.
● a (x-x') (x-x")
x and x' are the zeroes
■■■■■■■■■■■■■■■■■■■■■■■■■■
●y = a (x-x') (x-x")
x' and x" are khown but a is not.
We are given a point so replace x and y with its coordinates to find a.
So the steps are:
● 1) Write the factored form of the quadratic equation
● 2) replace x' and x" with their values.
● 3) replace x and y with the coordinates of a khwon point.
● 4) solve the equation for a.
The steps are write the factored form of the quadratic equation then, replace x' and x" with their values. To replace x and y with the coordinates of a known point. To solve the equation for a.
What is a quadratic equation?A quadratic equation is the second-order degree algebraic expression in a variable. the standard form of this expression is ax² + bx + c = 0 where a. b are coefficients and x is the variable and c is a constant.
Using the zeroes, we can write a factored form;
a (x-x') (x-x")
x and x' are the zeroes
y = a (x-x') (x-x")
x' and x" are known but a is not.
We are given a point so replace x and y with their coordinates to find a.
So the steps are:
1) Write the factored form of the quadratic equation
2) To replace x' and x" with their values.
3) To replace x and y with the coordinates of a known point.
4) To solve the equation for a.
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If this first answers correct what is the answer to the second question? Are they even connected?
Answer:
see below (I hope this helps!)
Step-by-step explanation:
9) We know that the perimeters of the square and triangle are equal so to find x, we can write:
4(x - 5) = x + x + 12
4x - 20 = 2x + 12
2x = 32
x = 16
10) To find the perimeter, we can substitute x = 16 into 4(x - 5) which would be 4(16 - 5) = 4 * 11 = 44.
. A discount brokerage selected a random sample of 64 customers and reviewed the value of their accounts. The mean was $32,000 with a population standard deviation of $8,200. What is a 90% confidence interval for the mean account value of the population of customers
Answer:
The 90% confidence interval is [tex]\$ \ 30313.9< \mu < \$ \ 33686.13[/tex]
Step-by-step explanation:
From the question we are told that
The sample size is n = 64
The sample mean is [tex]\= x = \$ 32, 000[/tex]
The standard deviation is [tex]\sigma= \$ 8, 200[/tex]
Given that the confidence interval is 90% then the level of significance is mathematically evaluated as
[tex]\alpha = 100 - 90[/tex]
[tex]\alpha = 10 \%[/tex]
[tex]\alpha = 0.10[/tex]
Next we obtain the critical value of [tex]\frac{ \alpha }{2}[/tex] from the normal distribution table , the value is
[tex]Z_{\frac{\alpha }{2} } = 1.645[/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \frac{ \sigma }{ \sqrt{n} }[/tex]
=> [tex]E = 1.645 * \frac{ 8200 }{ \sqrt{64} }[/tex]
=> [tex]E = 1686.13[/tex]
The 90% confidence interval is mathematically represented as
[tex]\= x - E < \mu < \= x + E[/tex]
=> [tex]32000 - 1689.13 < \mu < 32000 + 1689.13[/tex]
=> [tex]\$ \ 30313.9< \mu < \$ \ 33686.13[/tex]
if b<0 and |b| = 4b+15 what is the value of b
Answer:
|b|= 4b+15
-b=4b+15
-b-4b= 15
-5b= 15
b= 15/-5
b= -3
the ans -3
If [tex]a<0[/tex] the [tex]|a|=-a[/tex]
So
[tex]|b|=4b+15\\-b=4b+15\\5b=-15\\b=-3[/tex]
a scientist used 2 gallons of liquid for every 7 hours he works. he used__of a gallon each hour he works
Answer: 2/7 of a gallon (in decimal it’s 0.286)
Step-by-step explanation: This one’s really easy.
2/7 of 1 gallon. Checking: so that if you multiply it by 7 it equals to 2
The gallon he used each hour he works is 2/7.
What is unit rate?
A rate is a ratio that is used for comparing two different kinds of quantities which have different units. On the other hand, the unit rate illustrates how many units of quantity correspond to the single unit of another quantity.
The common examples used are:
Distance per second
Kilometer per hour
Meter per second
Earning per month
Given,
he used 2 gallons liquid for every 7 hours he works.
gallons used for per hour = 2/7
Hence, He used 2/7 gallons per hour.
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Write the polar form of a complex number in standard form for [tex]25[cos(\frac{5\pi }{6}) + isin(\frac{5\pi }{6})][/tex]
Answer:
Standard Complex Form : [tex]-\frac{25\sqrt{3}}{2}+\frac{25}{2}i[/tex]
Step-by-step explanation:
We want to rewrite this expression in standard complex form. Let's first evaluate cos(5π / 6). Remember that cos(x) = sin(π / 2 - x). Therefore,
cos(5π / 6) = sin(π / 2 - 5π / 6),
π / 2 - 5π / 6 = - π / 3,
sin(- π / 3) = - sin(π / 3)
And we also know that sin(π / 3) = √3 / 2. So - sin(π / 3) = - √3 / 2 = cos(5π / 6).
Now let's evaluate the sin(5π / 6). Similar to cos(x) = sin(π / 2 - x), sin(x) = cos(π / 2 - x). So, sin(5π / 6) = cos(- π / 3). Now let's further simplify from here,
cos(- π / 3) = cos(π / 3)
We know that cos(π / 3) = 1 / 2. So, sin(5π / 6) = 1 / 2
Through substitution we receive the expression 25( - √3 / 2 + i(1 / 2) ). Further simplification results in the following expression. As you can see your solution is option a.
[tex]-\frac{25\sqrt{3}}{2}+\frac{25}{2}i[/tex]
Mike took clothes to the cleaners three times last month. First, brought 4 shirts and of slacks and paid $11.45. Then brought 7 shirts, 2 pairs of slacks, and 2 sports and paid $35.39. Finally, brought 5 shirts and 2 sports and paid $21.43 . How much was charged for each shirt, each pair of slacks, and each sports coat?
Complete Question:
Mike took clothes to the cleaners three times last month. First, brought 4 shirts and 1 pair of slacks and paid $11.45. Then brought 7 shirts, 2 pairs of slacks, and 2 sports and paid $35.39. Finally, brought 5 shirts and 2 sports and paid $21.43 . How much was charged for each shirt, each pair of slacks, and each sports coat?
Answer:
The charges
For each Shirt = $1.49
For each pair of slacks = $5.49
For each sports coat = $6.99
Step-by-step explanation:
Let Shirt = a
Let pair of slacks = b
Let sports coat = c
First, brought 4 shirts and 1 pair of slacks and paid $11.45
= 4a + b = 11.45 ..........Equation 1
b = 11.45 - 4a
Then brought 7 shirts, 2 pairs of slacks, and 2 sports and paid $35.39
= 7a + 2b + 2c = 35.39.........Equation 2
5 shirts and 2 sports and paid $21.43
5a + 2c = 21.43............Equation 3
Hence:
4a + b = 11.45 ..........Equation 1
7a + 2b + 2c = 35.39.........Equation 2
Using elimination method
Multiply Equation 2 by the coefficient of b = 1 in Equation 1
Multiply Equation 1 by the coefficient of b = 2 in Equation 2
8a + 2b = 22.9 .......Equation 4
7a + 2b + 2c = 35.39.........Equation 2
Subtracting Equation 2 from Equation 4
= a - 2c = -12.49 ........Equation 5
a = -12.49 + 2c
Subtituting -12.49 + 2c for a in Equation 3
5a + 2c = 21.43............Equation 3
5(-12.49 + 2c) + 2c = 21.43
= -62.45 + 10c + 2c = 21.43
Collecting like terms
10c + 2c = 21.43 + 62.45
12c = 83.88
c = 83.88/12
c = 6.99
5a + 2c = 21.43............Equation 3
Substituting 6.99 for c in Equation 3
5a + 2(6.99) = 21.43
5a + 13.98 = 21.43
5a = 21.43 - 13.98
5a = 7.45
a = 7.45/5
a = 1.49
4a + b = 11.45 ..........Equation 1
Substituting 1.49 for a in Equation 1
4(1.49) + b = 11.45
b = 11.45 - 4(1.49)
b = 11.45 - 5.96
b = 5.49
Therefore, since the charges
For each shirt = a
The charges for each Shirt = $1.49
For each pair of slacks = b
The charges for each pair of slacks = $5.49
For each sports coat = c
The charges for each sports coat = $6.99
A recent survey of 1090 U.S. adults selected at random showed that 623 consider the occupation of firefighter to have very great prestige. Estimate the probability (to the nearest hundredth) that a U.S. adult selected at random thinks the occupation of firefighter has very great prestige.
Answer:
0.572
Step-by-step explanation:
From the question,
We have
n = 1090 of US adults
x = 623 selected from this population at random who consider the occupation to be one of great prestige
So we have that
The probability of X = x/n
= 623/1090
= 0.572
We conclude that 0.572 is the probability that a US adult selected at random thinks the occupation has great prestige.
what is the magnitude of the vector?
Answer:
[tex]\boxed{\sqrt{65}}[/tex]
Step-by-step explanation:
Magnitude is solved with the following equation: [tex]\sqrt{x^{2}+y^{2}}[/tex]
Therefore, just plug in your x and y-values and solve.
[tex]\sqrt{4^{2}+7{^{2}}[/tex]
[tex]\sqrt{16 + 49}[/tex]
[tex]\sqrt{65}[/tex]
Because [tex]\bold{\sqrt{65}}[/tex] cannot be simplified further, this is the magnitude of the vector.
PLEASE HELP!!! Sarah had a balance of $155 in her bank account at the start of the week. She withdrew $65.50 on Monday, $23.25 on Wednesday, and $26.45 on Thursday. On Friday she deposited $165.30. Write an expression that represents Sarah's spending. *
Answer:
155.00-65.50-23.25-26.45+165.30
Step-by-step explanation:
Answer:
155 + 165.3 - 65.5 - 23.25 - 26.45
Step-by-step explanation:
She had $155 dollars in the starting = +155
She withdrew $65.5 = -65.5
She withdrew another $23.25 = -23.25
She withdrew another $26.45 = -26.45
She deposited $165.3 = +165.3
The expression looks like:
155 + 165.3 - 65.5 - 23.25 - 26.45
We could solve the expression:
155 + 165.3 - 65.5 - 23.25 - 26.45
=> 320.3 - 88.75 - 26.45
=> 320.3 -115.2
=> 205.1
At the end of the week, she had a total of $205.10.
While you can use the correlation coefficient as its own test statistic, what is the other appropriate test statistic often used to examine the significance of a correlation
Answer:
T-test
Step-by-step explanation:
Significance of correlation between two variables x and y measures the strength and direction of their relationship. This is used to make future forecasts of the behaviour of a variable under study.
Correlation coefficient can be used to measure significance of correlation, but we can also use the t-test.
T-test is a statistics that is inferential. It measures the significance of difference between the means of two groups.
T-test is the statistic of choice when carrying out hypothesis testing.
T distribution values and degrees of freedom are used to determine statistical significance.
For example the means of two samples can be compared to determine of the come from the same population
find the value of x - Secant and Tangent Angles in Circles
Answer:
C. 70°
Step-by-step explanation:
The inscribed angle marked 15° intercepts an arc that is double that measure, so the intercepted arc on the right is 2×15° = 30°.
The external angle marked 20° is half the difference of the intercepted arcs, so is ...
20° = (1/2)(x - 30°)
40° = x - 30° . . . . . . multiply by 2
70° = x . . . . . . . . . . . add 30°
The value of x is 70°.
Lisa built a rectangular flower garden that is 4 meters wide and has a perimeter of 26 meters.
What is the length of Lisa's flower garden?
Answer:
9 m
Step-by-step explanation:
Given that
Width of rectangular flower garden, w = 4 m
Perimeter of rectangular flower garden, p = 26 m
To find:
Length of Lisa's flower garden = ?
Solution:
First of all, let us understand perimeter, length and width of a rectangle.
Let ABCD be a rectangle. Please refer to the attached image.
Opposite sides of a rectangle are equal to each other.
AB = CD = Length
Let the length be [tex]l[/tex] m.
BC = DA = Width = 4 m
Perimeter of a closed image is equal to the sum of all the sides of the image.
So, perimeter of ABCD:
[tex]p = AB + BC + CD + DA \\\Rightarrow \bold{ p = 2 \times (Length +Width)}[/tex]
[tex]26 = 2 \times (l +4)\\\Rightarrow 2l =26-8\\\Rightarrow \bold{l = 9 m}[/tex]
The weight of a full steel bead tire is approximately 800 grams, while a lighter wheel weighs only 700 grams. What is the weight of each tire in pounds? There are 453.592 grams in one pound. Round answers to 2 decimal places. 800 grams = ______ pounds 700 grams = _____ pounds
Answer:
800= about 1.76 lbs
700= about 1.54 lbs
(there are about 453.5 grams in a pound
Step-by-step explanation:
Answer:
800 grams = 1.76 pounds
700 grams = 1.54 pounds
Step-by-step explanation:
i googled it
Find the standard form of the equation of the ellipse with the given characteristics and center at the origin. Foci: (±7, 0); major axis of length 18
Answer: [tex]\dfrac{x^2}{81}+\dfrac{y^2}{32}=1[/tex]
Step-by-step explanation:
The standard form of equation of ellipse with foci (±c,0) as:
[tex]\dfrac{x^2}{a^2}+\dfrac{y^2}{b^2}=1[/tex]
, where major axis = 2a and minor axis = 2b
Given: Foci: (±7, 0); major axis of length 18
i.e. c= 7 and 2a =18 ⇒a= 9
Also,
[tex]c^2=a^2-b^2\Rightarrow\ b^2= a^2-c^2\\\\\Rightarrow\ b^2={9^2-7^2}={81-49}\\\\\Rightarrow\ b^2=32[/tex]
Put value of [tex]a^2[/tex] and [tex]b^2[/tex] , we get the required equation :
[tex]\dfrac{x^2}{81}+\dfrac{y^2}{32}=1[/tex]
When all possible differences between pairs of population means are evaluated not with an F test, but with a series of regular t tests, the probability of at least one:
Answer:
When all possible differences between pairs of population means are evaluated not with an F test, but with a series of regular t tests, the probability of at least one:
A. type I error is larger than the specified level of significance.
B. type II error is larger than the specified level of significance.
C. type I error is smaller than the specified level of significance.
D. type II error is smaller than the specified level of significance.
Answer : Type I error is larger than the specified level of significance.( A )
Step-by-step explanation:
An F test is a test that is used to test whether the variances between pairs of populations are equal while a T test is a test used to check if a pair of population are equal not considering the fact that the variances of the population are different .
When a T test is used to evaluate all possible differences between pairs of population instead of F test there is a probability of atleast one type 1 error larger than the specified level of significance.
rite
8x8*8X8X8 as
power
Answer:
8×8×8×8×8
= 8^5
because there are five 8 number
I hope this helps
if u have question let me know in comments ^_^
[tex]8\cdot8\cdot8\cdot8\cdot8=8^5[/tex]
You are conducting a hypothesis where the null reads H0: μ 10 You have Just concluded that you should fail to reject the null hypothesis because Z* 1.49 and Zc 1.645 Select the best conclusion statement.
A. There is overwhelming evidence that the mean is not 10.
B. There is not overwhelming evidence that the mean is different than 10.
C. Because the calculated value of Z was larger than the Zc, I rejected the null hypothesis
D. Because the Z* was only a little bigger than the Zc, the test supports the null hypothesis and we conclude u-10
Answer:
Option D - Because the Z* was only a little bigger than the Zc, the test supports the null hypothesis and we conclude μ = 10
Step-by-step explanation:
In z-value problems, the normal practice is that If the calculated z-value is less than the critical z-value, we will reject the null hypothesis and accept the alternative hypothesis but if it's greater than the critical z-value, we will fail to reject the null hypothesis and say that the test was not statistically significant.
In this problem, the calculated z-value of -1.49 is greater than -1.645, so we will fail to reject the null hypothesis and say that the test was not statistically significant.
Thus, in this question, we fail to reject the null hypothesis because the calculated value of z was bigger the value of z_c.
For this problem, use the tables and charts shown in this section. (Use picture provided)
A United States Citizen returning to the States declares the following items at the customs office:
3 shirts at $8.50 each
2 dresses at $27.50 each
1 pair of gold cuff links at $17.50 per pair
If he has not used his duty free exemption yet, how much duty should he pay?
0 $0.00
$5.00
$10.00
$300
Answer:
0
Step-by-step explanation:
0 because there is a $100 duty free exemption.
answer:
For this problem, use the tables and charts shown in this section.
A United States Citizen returning to the States declares the following items at the customs office:
3 shirts at $8.50 each
2 dresses at $27.50 each
1 pair of gold cuff links at $17.50 per pair
If he has not used his duty free exemption yet, how much duty should he pay?
$0.00 !
$5.00
$10.00
$300
The SAT Reasoning Test (formerly called the Scholastic Aptitude Test) is perhaps the most widely used standardized test for college admissions in the United States. Scores are based on a normal distribution with a mean of 1500 and a standard deviation of 300. Clinton College would like to offer an honors scholarship to students who score in the top 10 percent of this test. What is the minimum score that qualifies for the scholarship?
Minimum Score:
Answer:
The score is [tex]x = 1884[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 1500[/tex]
The standard deviation is [tex]\sigma = 300[/tex]
From the question we are told that the score follow a normal distribution
i.e [tex]X \~ \ N( 1500 , 300)[/tex]
The proportion of score in the top 10% is mathematically
[tex]P(X > x ) = P( \frac{X - \mu}{\sigma } > \frac{x - \mu}{\sigma } ) = 0.10[/tex]
Where x is the minimum score required to be in the top 10%
Now the [tex]\frac{X - \mu}{\sigma } = Z (The \ Standardized \ value \ of \ X)[/tex]
So
[tex]P(X > x ) = P( Z > \frac{x - \mu}{\sigma } ) = 0.10[/tex]
So
[tex]P(X > x ) = P( Z > \frac{x - 1500}{300} ) = 0.10[/tex]
So the critical value of 0.10 from the normal distribution table is [tex]Z_{0.10} = 1.28[/tex]
So
[tex]\frac{x - 1500}{300} = 1.28[/tex]
[tex]x = 1884[/tex]
A plane is flying at the height of 5000 meter above the sea level. at a particular point, it is excatly above a submarine floating 1200 meter below the sea level. what is the vertical distance between them ?
Answer:
3800 meters
Step-by-step explanation:
The circumference of a redwood tree trunk is 16π ft, and it is 100 ft tall. What is the approximate volume of the redwood tree trunk? 2,560π ft3 640π ft3 25,600π ft3 6,400π ft3
Answer:
volume of redwood tree is 6400 π ft^3(option 4)
Step-by-step explanation:
concept =
volume of cylinder = πr^2l
where r is the radius and l is the length of cylinder
circumference of cylinder = 2πr
_____________________________________
shape of redwood tree can be taken as cylindrical
given
circumference of a redwood tree trunk is 16π ft
2πr = 16π
=> r = 16π/2π = 8
Thus, radius is 8 feet
Therefore volume of redwood tree = πr^2l = π8^2*100 = π*64*100
volume of redwood tree =6400 π ft^3
Answer:
6,400π ft3
Step-by-step explanation:
took test and got it right
Your job in a company is to fill quart-size bottles of oil from a full -gallon oil tank. Then you are to pack quarts of oil in a case to ship to a store. How many full cases of oil can you get from a full -gallon tank of oil?
Answer:
See below.
Step-by-step explanation:
1 gal = 4 qt
With a full gallon oil tank, you can fill 4 1-qt bottles.
The problem does not mention the number of quarts that go in a case, so there is not enough information to answer the question.
Also, is the full tank really only 1 gallon, or is there a number missing there too?
Find the missing side of the triangle. A. √321 yd B. √221 yd C. 3√38 yd D. √21 yd
Answer:
(B) [tex]\sqrt{221}[/tex] yards
Step-by-step explanation:
Since this is a right triangle, we can use the Pythagorean Theorem to find the length of x.
The Pythagorean Theorem states that [tex]a^2 + b^2 = c^2[/tex], where a and b are our legs and c is the hypotenuse.
We need to find c, and we already know a and b, so let's substitute.
[tex]10^2 + 11^2 = c^2\\\\100+121=c^2\\\\221=c^2\\\\c=\sqrt{221}[/tex]
Hope this helped!
Complete the statement to describe the expression abc+def
The expression consists of ____ terms,and each term contains___ factors
Answer:
3 each
Step-by-step explanation:
The answer is already on this site
Brainliest for the correct answer!! A calculator was used to perform a linear regression on the values in the table. The results are shown to the right of the table.What is the line of best fit?A.y = –0.984x + 13.5B.y = –2.9x + 13.5C.–0.984 = –2.9x + 13.5D.y = 13.5x – 2.9
Answer:
B. y = –2.9x + 13.5
Step-by-step explanation:
You can try to use the calculator to determine the best line for the values given; you will se that the calculator form, for the linear function is
y = a + bx, where a is the y intercept and b is the slope.
To determine the slope, we apply a formula, to calculate the product of the two xy and, x², plus the sum of each column.
x y xy x²
1 . 11 = 11 → x² = 1² = 1
2 . 8 = 16 → x² = 2² = 4
3 . 4 = 12 → x² = 3² = 9
4 . 1 = 4 → x² = 4² = 16
5 . 0 = 0 → x² = 5² = 25
Total x = 1 + 2 + 3 + 4 + 5 = 15
Total y = 11 + 8 + 4+ 1 + 0 = 24
Sum of xy = 11 + 16 + 12 + 4 + 0 = 43
Sum of x² = 1 + 4 + 9 + 16 + 25 = 55
n = 5
So b = 5 (43) - (15) . (24) / 5 (55) - 15² = -2.9
a = y media - b . x media → a = 24/5 - (-2.9) . 15/5 = 13.5