Answer:
x= -3 ± [tex]\sqrt{21}[/tex]
Step-by-step explanation:
[tex]x^{2}[/tex]+6x=12
We add 9 [[tex](6/2)^{2}[/tex]] to both sides to complete the square as [tex]x^{2}[/tex]+6x+9 = [tex](x+3)^{2}[/tex].
[tex](x+3)^{2}[/tex]=21
Now we take the square root of both sides:
x+3=±[tex]\sqrt{21}[/tex]
x= -3 ± [tex]\sqrt{21}[/tex]
Answer:
x = -3 ± [tex]\sqrt{21}[/tex]
Step-by-step explanation:
[tex]x^2+6x=12[/tex]
[tex](\frac{b}{2} )^{2}[/tex] = 9
[tex]x^2+6x + 9 =12 + 9[/tex]
[tex](x+3)^{2} =21[/tex]
x + 3 = [tex]\sqrt{21}[/tex]
x = -3 ± [tex]\sqrt{21}[/tex]
Joe's Auto Insurance Company customers sometimes have to wait a long time to speak to a
customer service representative when they call regarding disputed claims. A random sample
of 25 such calls yielded a mean waiting time of 22 minutes with a standard deviation of 6
minutes. Construct a 95% and 99% confidence interval for the population mean of such
waiting times. Explain what these interval means.
Answer:
The 95% confidence interval for the population mean of such waiting times is between 19.5 and 24.5 minutes. This means that we are 95% sure that the true mean waiting time of all calls for this company is between 19.5 and 24.5 minutes.
The 99% confidence interval for the population mean of such waiting times is between 18.6 and 25.4 minutes. This means that we are 99% sure that the true mean waiting time of all calls for this company is between 18.6 and 25.4 minutes.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 25 - 1 = 24
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 24 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.0639
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 2.0639\frac{6}{\sqrt{25}} = 2.5[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 22 - 2.5 = 19.5 minutes
The upper end of the interval is the sample mean added to M. So it is 22 + 2.5 = 24.5 minutes
The 95% confidence interval for the population mean of such waiting times is between 19.5 and 24.5 minutes. This means that we are 95% sure that the true mean waiting time of all calls for this company is between 19.5 and 24.5 minutes.
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 24 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995[/tex]. So we have T = 2.797
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 2.797\frac{6}{\sqrt{25}} = 3.4[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 22 - 3.4 = 18.6 minutes
The upper end of the interval is the sample mean added to M. So it is 22 + 3.4 = 25.4 minutes
The 99% confidence interval for the population mean of such waiting times is between 18.6 and 25.4 minutes. This means that we are 99% sure that the true mean waiting time of all calls for this company is between 18.6 and 25.4 minutes.
I WILL MARK THE ANSWER AS BRAINLIEST IF RIGHT
PLEASE HELP ME BE CORRECT BEFORE ANSWERING PLEASE
9514 1404 393
Answer:
D neither
Step-by-step explanation:
Reflection across a vertical line is required to change the figure left-to-right without changing it top-to-bottom. Translation along a directed line segment must then map corresponding points.
Sequence A involves reflection over a horizontal line, so can be rejected immediately. Sequence B does the translation so that point N gets moved to the location of point B. However, point N corresponds to point D (see the similarity statement), so that translation is inappropriate.
Neither sequence will map KLMN to ABCD.
(a)234.3x13 (b) 31.38 X 5 (c) 0.653X 45 (d) 21.45X 10
(e) 25.41X 18 (f) 93.2 X 47 (g) 234.2X 342 (h) 89.4X20
(a)1.1 X 3.0 (b) 2.5 X 1.4 (c) 3.4X 4.6 (d) 2.4X4.8
(e) 2.6 X 12.3 (f) 6.72 X 56.1 (e) 24.59 X 31.2 (f) 27.15 X 3.7
Pleaseeeeee o someone help me
Answer:
63 cm and 63 cm
Step-by-step explanation:
Both are 63 cm because 9*7 is 63, and those are the measurements of both faces
If a projectile is fired with an initial speed of vo ft/s at an angle α above the horizontal, then its position after t seconds is given by the parametric equations x=(v0cos(α))t andy=(v0sin(α))t−16t2
(where x and y are measured in feet).
Suppose a gun fires a bullet into the air with an Initial speed of 2048 ft/s at an angle of 30 o to the horizontal.
(a) After how many seconds will the bullet hit the ground?
(b) How far from the gun will the bullet hit the ground? (Round your answer to one decimal place.)
(c) What is the maximum height attained by the bullet? (Round your answer to one decimal place.)
Answer:
a) The bullet hits the ground after 64 seconds.
b) The bullet hits the ground 113,511.7 feet away.
c) The maximum height attained by the bullet is of 16,384 feet.
Step-by-step explanation:
Equations of motion:
The equations of motion for the bullet are:
[tex]x(t) = (v_0\cos{\alpha})t[/tex]
[tex]y(t) = (v_0\sin{\alpha})t - 16t^2[/tex]
In which [tex]v_0[/tex] is the initial speed and [tex]\alpha[/tex] is the angle.
Initial speed of 2048 ft/s at an angle of 30o to the horizontal.
This means that [tex]v_0 = 2048, \alpha = 30[/tex].
So
[tex]x(t) = (v_0\cos{\alpha})t = (2048\cos{30})t = 1773.62t[/tex]
[tex]y(t) = (v_0\sin{\alpha})t - 16t^2 = (2048\sin{30})t - 16t^2 = 1024t - 16t^2[/tex]
(a) After how many seconds will the bullet hit the ground?
It hits the ground when [tex]y(t) = 0[/tex]. So
[tex]1024t - 16t^2 = 0[/tex]
[tex]16t^2 - 1024t = 0[/tex]
[tex]16t(t - 64) = 0[/tex]
16t = 0 -> t = 0 or t - 64 = 0 -> t = 64
The bullet hits the ground after 64 seconds.
(b) How far from the gun will the bullet hit the ground?
This is the horizontal distance, that is, the x value, x(64).
[tex]x(64) = 1773.62(64) = 113511.7[/tex]
The bullet hits the ground 113,511.7 feet away.
(c) What is the maximum height attained by the bullet?
This is the value of y when it's derivative is 0.
We have that:
[tex]y^{\prime}(t) = 1024 - 32t[/tex]
[tex]1024 - 32t = 0[/tex]
[tex]32t = 1024[/tex]
[tex]t = \frac{1024}{32} = 32[/tex]
At this instant, the height is:
[tex]y(32) = 1024(32) - 16(32)^2 = 16384[/tex]
The maximum height attained by the bullet is of 16,384 feet.
Given the data points below, compute the sum of squared errors for the regression equation
Y
=
2
+
3
X
.
X
0
3
7
10
Y
5
5
27
31
Answer:
The sum of squared errors for the regression equation is 62.
Step-by-step explanation:
The sum of squared errors can be computed as follows:
X Y Y* = 2 + 3X Y - Y* (Y - Y*)^2
0 5 2 3 9
3 5 11 -6 36
7 27 23 4 16
10 31 32 -1 1
20 68 68 0 62
From the above, we have:
Error = Y - Y*
Error^2 = (Y - Y*)^2
Sum of squared errors = Sum of Error^2 = Total of (Y - Y*)^2 = 62
Therefore, the sum of squared errors for the regression equation is 62.
if f(x)=-5^x-4 and g(x)=-3x-2,find (f+g) (x)
Answer: (f-g)(x) = - 5^x + 3x - 2
Step-by-step explanation:
if f(x) = -5^x - 4 and g(x)= - 3x - 2,find (f-g)(x)
(f-g)(x) = -5^x - 4 - (-3x - 2)
(f-g)(x) = -5^x - 4 + 3x + 2
(f-g)(x) = - 5^x + 3x - 2
A family has inherited $300,000. If they choose to invest the $300,000 at 12\% per year compounded quarterly, how many quarterly withdrawals of $25000 can be made? (Assume that the first withdrawal is three months after the investment is made).
Step-by-step explanation:
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h=255-21t-16t^2
PLEASE HELP!!
Answer:
3.15 seconds is the answer.
Explanation
when the ball touches the ground, h =0
hence,
0=255-21t-16t²
16t²+21t-225=0
here a=16 ,b=21, c= -225
[tex]t= \frac{ - b± \sqrt{ {b }^{2} - 4ac} }{2a} \\ \\ t= \frac{ - 21± \sqrt{ {21}^{2} - 4 \times 16 \times - 225} }{2 \times 16} \\ = \frac{ - 21 ± \sqrt{441 - ( - 14400)} }{32} \\ = \frac{ - 21± \sqrt{14841} }{32} \\ = \frac{ - 21±121.82}{32} \\ \\ t = \frac{ - 21 + 121.82}{32} \: or \: \: t = \frac{ - 21 - 121.82}{32} \\ t = 3.15 \: \: or \: \: t = - 4.46[/tex]
time cannot be negative, hence t = -4.46 can be avoided
The ball takes 3.15 seconds to hit the ground.
Negate this conditional statement. Please show proper work and an explanation. Those who attempt to just respond in order to get a lot of points shall be reported. Thank you.
Answer:
a AND ~c
Step-by-step explanation:
you can find the full explanation in wikipedia:
https://en.m.wikipedia.org/wiki/Material_conditional
under "Negated conditionals"
The circumference of a circle is 14 inches. Find the circle's radius and diameter.
Please help :)
Twice the difference of a number and 6
Answer:
2x=6. I think friend it is correct.
Answer:
2(×-6)
Step-by-step explanation:
Correct me if im wrong thanks ●~●
A bank gives you a loan of 1,500,000 Baht to buy a house. The interest rate of the loan is 0.01% per day (Using 1 year = 365 days)
How much interest you pay after 10 years
Answer:
15.000 is cost so relate it with 265..hope it is help u.
Christian and Tanae both leave Disneyland at the same time. Christian travels north at 65 mph. Tanae travels south at 55 mph. How long will it take them to be 540 miles apart? Which of the following equations would you use to solve this word problem?
65t + 55(t − 1) = 540.
65t + 55t = 540.
65t + 55(t + 1) = 540.
None of these choices are correct.
Answer:
Step-by-step explanation:
B looks like it would work.
You add speeds * time when you are travelling in opposite directions.
I don't know why you would add or subtract 1 as in A and C
120 * t = 540
t = 540/120
t = 4.5 hours.
So after 4.5 hours they are 540 miles apart.
Answer:
b
Step-by-step explanation:
Construct the discrete probability distribution for the random variable described. Express the probabilities as simplified fractions. The number of tails in 5 tosses of a coin.
Answer:
[tex]P(X = 0) = 0.03125[/tex]
[tex]P(X = 1) = 0.15625[/tex]
[tex]P(X = 2) = 0.3125[/tex]
[tex]P(X = 3) = 0.3125[/tex]
[tex]P(X = 4) = 0.15625[/tex]
[tex]P(X = 5) = 0.03125[/tex]
Step-by-step explanation:
For each toss, there are only two possible outcomes. Either it is tails, or it is not. The probability of a toss resulting in tails is independent of any other toss, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
Fair coin:
Equally as likely to be heads or tails, so [tex]p = 0.5[/tex]
5 tosses:
This means that [tex]n = 5[/tex]
Probability distribution:
Probability of each outcome, so:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{5,0}.(0.5)^{0}.(0.5)^{5} = 0.03125[/tex]
[tex]P(X = 1) = C_{5,1}.(0.5)^{1}.(0.5)^{4} = 0.15625[/tex]
[tex]P(X = 2) = C_{5,2}.(0.5)^{2}.(0.5)^{3} = 0.3125[/tex]
[tex]P(X = 3) = C_{5,3}.(0.5)^{3}.(0.5)^{2} = 0.3125[/tex]
[tex]P(X = 4) = C_{5,4}.(0.5)^{4}.(0.5)^{1} = 0.15625[/tex]
[tex]P(X = 5) = C_{5,5}.(0.5)^{5}.(0.5)^{0} = 0.03125[/tex]
Candice is preparing for her final exam in Statistics. She knows she needs an 74 out of 100 to earn an A overall in the course. Her instructor provided the following information to the students. On the final, 200 students have taken it with a mean score of 68 and a standard deviation of 4. Assume the distribution of scores is bell-shaped. Calculate to see if a score of 74 is within one standard deviation of the mean.
a) Yes, 74 is the upper limit of one standard deviation from the mean.
b) Yes, the upper level of one standard deviation is 72.
c) Yes, 74 is greater than the 64, one standard deviation below the mean.
d) No, 74 is greater than the mean of 68.
Answer:
Hence the correct option is option b) Yes, the upper level of one standard deviation is 72.
A score of 74 is not within one standard deviation of the mean.
Step-by-step explanation:
Here the given details are,
Mean = 68
SD = 4
Distribution is normal.
Z-score for x = 74 is given as below:
[tex]Z = (X - mean)/SD\\Z = (74 - 68)/4\\Z = 1.5[/tex]
So, the score of 74 is 1.5 standard deviations from the mean.
[tex]Mean + 1\timesSD = 68 + 1\times4 = 72Mean - 1\timesSD = 68 - 1\times4 = 64[/tex]
Therefore the score is not lies between 64 and 72.
Yes, the upper level of one standard deviation is 72.
There are 48 students o the school bus, 28 girls and 20 boys. what is the ratio of boys ad girls on the bus ?
Step-by-step explanation:
28:20
Once simplified its 7:5
Suppose a research company takes a random sample of 45 business travelers in the financial industry and determines that the sample average cost of a domestic trip is $1,192, with a sample standard deviation of $279. Construct a 98% confidence interval for the population mean (for domestic trip) from these sample data. Round your answers to 3 decimal places.
Answer:
98% confidence interval for the population mean =(1095.260,1288.740)
Step-by-step explanation:
We are given that
n=45
[tex]\mu=1192[/tex]
Standard deviation,[tex]\sigma=279[/tex]
We have to construct a 98% confidence interval for the population mean.
Critical value of z at 98% confidence, Z =2.326
Confidence interval is given by
[tex](\mu\pm Z\frac{\sigma}{\sqrt{n}})[/tex]
Using the formula
98% confidence interval is given by
[tex]=(1192\pm 2.326\times \frac{279}{\sqrt{45}})[/tex]
[tex]=(1192\pm 96.740)[/tex]
=[tex](1192-96.740,1192+96.740)[/tex]
=[tex](1095.260,1288.740)[/tex]
Hence, 98% confidence interval for the population mean (1095.260,1288.740)
What is the most specific name for a quadrilateral with one pair of parallel sides?
A. trapezoid
B. rectangle
C. parallelogram
D. quadrilateral
help me pls
Answer:
C: parallelogram
Step-by-step explanation:
Peter organizes morning hikes for his friends every Saturday. When the hiking trail is 3 km long, 19 friends join him and when the trail is 5 km long, only 7 friends tag along. There exists a linear relationship between the distance of the hiking trail (in km) and the number of friends who tag along. The number of friends depend on the distance of the trail. Determine how many friends will tag along to a hiking trail of 2 km.
Answer:
25
Step-by-step explanation:
x = distance of the hike
y = number of friends coming along
so, we are looking for a linear relationship between these two.
y = ax + b
we need to find the factor a and the constant offset b.
19 = a×3 + b
7 = a×5 + b
7 - b = a×5
a = (7-b)/5
19 = (7-b)×3/5 + b
19 = (21 - 3b)/5 + b
95 = 21 - 3b + 5b
74 = 2b
b = 37
a= (7-37)/5 = -30/5 = -6
so, the relationship is
y = -6x + 37
for 2km hiking
y = -6×2 + 37 = -12 + 37 = 25 friends
The solution set of the inequality 1 + 2y
Answer:
is it four I am not quite sure
Anyone know this question?
Answer:
[tex](f + g)(4) = 191[/tex]
Step-by-step explanation:
Given
[tex]f(x) = 5x^2 - 5x + 15[/tex]
[tex]g(x) = 6x^2 + 7x - 8[/tex]
Required
[tex](f + g)(4)[/tex]
First, calculate [tex](f + g)(x)[/tex]
This is calculated as:
[tex](f + g)(x) = f(x) + g(x)[/tex]
So, we have:
[tex](f + g)(x) = 5x^2 - 5x + 15+6x^2 + 7x - 8[/tex]
Collect like terms
[tex](f + g)(x) = 5x^2 +6x^2 - 5x+ 7x + 15 - 8[/tex]
[tex](f + g)(x) = 11x^2 + 2x + 7[/tex]
Substitute 4 for x
[tex](f + g)(4) = 11*4^2 + 2*4 + 7[/tex]
[tex](f + g)(4) = 191[/tex]
what is the simplified form of the following expression 3 sqrt 4x/5
Answer:
Kindly check the attached picture
Step-by-step explanation:
The solution to the problem has been explicitly solved in the picture attached below :
We need to find a number that makes the denominator a perfect cube in other to simplify the expression which is 25/25.
Kindly check the attached picture for detailed explanation
Is AFGH ~ AJKL? If so, identify the similarity postulate or theorem that
applies.
G
K
10
6
30°
30°
Н
A. Similar - SAS
B. Cannot be determined
C. Similar - SSS
D. Similar - AA
Answer: B. Cannot be determined
Explanation:
We can't use SAS since we don't have two pairs of proportional sides. We only know one pair of sides. This also rules out SSS as well since we'd need 3 pairs of proportional sides.
We can't use AA because we don't have two pairs of congruent angles.
Currently, we simply don't have enough information to determine if the triangles are similar or not.
The diagram below shows rectangle ABC is a midtsin of
BC, such that D,E and F are on the same line API AD
i = 53, 13" BE-sm
and DE 2 EF
84
2176
F
with reasons
3.1 Prove
AB - BF
3.2. Calculate AD
3.3 Complece. In are rigter angled A BEF, son 53, 13" - BE
Answer:
4x2+3=
Step-by-step explanation:
Can someone help me with this? Thanks!
9514 1404 393
Answer:
x ∈ {5, 7}(5,7)Step-by-step explanation:
The graph shows the function value is zero for x=5 and x=7. These are the elements of the solution set.
x ∈ {5, 7}
__
The graph is below the x-axis between these points, so that is the region where f(x) < 0
5 < x < 7 . . . . . for f(x) < 0
In interval notation: (5, 7).
Round 10,998 to nearest ten
Answer:
11,000
Step-by-step explanation:
NEED HELP ASAP GIVING BRAINLIEST!!!!!!!!!!!!!!!!!!
Answer:
option D
Step-by-step explanation:
[tex]sin^2 ( \frac{3\pi}{2}) + cos^2(\frac{3\pi}{2}) = 1\\\\( -1)^2 + 0^2 = 1[/tex]
Explanation:
[tex]sin x = cos( \frac{\pi}{2} - x)\\\\sin(\frac{3\pi}{2}) = cos ( \frac{\pi}{2} - \frac{3\pi}{2})\\[/tex]
[tex]=cos(\frac{\pi - 3\pi}{2})\\\\ =cos(\frac{2\pi}{2})\\\\=cos \ \pi\\\\= - 1[/tex]
Therefore ,
[tex]sin^2( \frac{3\pi}{2}) = ( - 1)^2[/tex]
Area of composite shapes ?
Answer: 58
Step-by-step explanation: you add them all together
Its 108 the other answer is the perimeter not the area.
) A patient drank 12 ounces of orange juice. How many milliliters did the patient drink?
Answer:
He drank 354.882 mills of orange juice
Step-by-step explanation: One ounce is equal to 29.5735 mills, so you multiply 29.5735 by 12
Answer: 355 Millileters
