To find the distance AB across a river, a distance BC of 415 m is laid off on one side of the river. It is found that B = 112.2° and C = 18.3°. Find AB.
Answers
The distance AB across the river is approximately 171.4 meters
The known parameters are;
The distance BC laid off on one side of the river = 415 m
The measure of ∠B = 112.2°
The measure of angle ∠C = 18.3°
The unknown parameter;
The distance AB across the river
Strategy;
Taking the points A, B, and C, being the vertices of the triangle, ΔABC, and apply sine rule to find distance AB;
By the angle sum property, the measure of angle, ∠A = 180° - (∠B + ∠C)
∴ ∠A = 180° - (112.2° + 18.3°) = 49.5°
By sine rule, we get;
[tex]\mathbf{\dfrac{a}{sin (\alpha)} = \dfrac{b}{sin (\beta)} = \dfrac{c}{sin (\gamma)}}[/tex]
Therefore;
[tex]\mathbf {a = sin (\alpha) \times \dfrac{b}{sin (\beta)}}[/tex]
Plugging in α = AB, [tex]\alpha[/tex] = ∠C = 18.3°, b = BC = 415, β = ∠A = 49.5°, we get;
[tex]AB = sin (18.3 ^{\circ}) \times \dfrac{415}{sin (49.5^{\circ})} \approx 171.4[/tex]
The distance across the river, AB ≈ 171.4 m
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Related Questions
10. What is the multiple zero and multiplicity of f(x) = (x - 3)(x - 3)(x + 5)?
Multiple zero is -3; multiplicity is 2
Multiple zero is 5; multiplicity is 1
Multiple zero is -5; multiplicity is 1
Multiple zero is 3; multiplicity is 2
Answers
Answer:
x=3, multiplicity of 2
x=-5, multiplicity of 1
Step-by-step explanation:
f(x) = (x - 3)(x - 3)(x + 5)
Rewriting
f(x) = (x - 3)^2(x + 5)
Setting equal to zero
0 = (x - 3)^2(x + 5)
Using the zero product property
(x-3)^2 = 0 x+5 = 0
x-3 = 0 x= -5
x=3 x-5
Since x-3 was squared, the multiplicity is 2
Answer:
x=3, multiplicity of 2
x=-5, multiplicity of 1
Step-by-step explanation
i need help and thx you freinds
Answers
Answer:
Below
Step-by-step explanation:
Find the areas of the triangles on the sides
A = bh / 2
= (3)(5) / 2
= 7.5
There are 2 of these so it would just be 15
Now for the square
A = lw
= (5)(6)
= 30
Add em all up
Total area = 15 + 30
= 45 cm^2
Hope this helps!
Which ordered pair is a solution to the system of inequalities? y > 2x
y > 7
A. (0, 0) B. (4, 8) C. (3, 7) D. (1, 9)
Answers
Answer:
D( 1,9)
Step-by-step explanation:
First y must be greater than 7 which eliminates A and C
y must be greater than 2 times the x value
2*4 = 8 so B is eliminated
2*1 = 2 which is less than 9 Choice D is a solution
1 calculate the weight of a dog on the earth and on the moon if it has a mass of 28kg
Answers
To solve the problem.
W=m×g
W=28×10
W=280.
The weight of a dog on the surface of earth is 280N.
Answer:
274.68N and 45.36N respectively
Step-by-step explanation:
Weight of any object is the mass in kilograms(kg) multiplied by the gravity in meter per square second(m/s^2). The gravity on earth is 9.81m/s^2 and on moon is 1.62m/s^2...so since the gravity varies the weight of the dog will also vary. The wight on earth would be 28kg multiplied by 9.81m/s^2 which would be 274.68N and the weight on moon would be 28kg multiplied by 1.62m/s^2 which would be 45.36N.
what is the mean in 0.33, 0.33, 0.54, 0.46, 0.30, 0.77, 0.42, 0.44, 0.60, 0.32, 0.47, 0.64, 0.61, 0.69, 0.41, 0.39, 0.66, 0.60, 0.61, 0.70
Answers
Answer:
0.5145
Step-by-step explanation:
Mean is also known as average. It is expressed as:
Mean = Sum of data/Sample size
Sum of data = 0.33+0.33+0.54+0.46+0.30+0.77+0.42+0.44+0.60+0.32+0.47+0.64+0.61+0.69+0.41+0.39+0.66+0.60+0.61+0.70
Sum of data = 10.29
Sample size = 20
Mean = 10.29/20
Mean = 0.5145
Hence the mean of the data is 0.5145
Plz help
Need answers ASAP
Answers
Answer:
1. cube
2. square pyramid
4. cone
5. cube
2. Square Pyramid
4. Cone
5. Cube
The scores of a high school entrance exam are approximately normally distributed with a given mean Mu = 82.4 and standard deviation Sigma = 3.3. What percentage of the scores are between 75.8 and 89?
Answers
Notice that
75.8 = 82.4 - 6.6 = 82.4 - 2 × 3.3
89 = 82.4 + 6.6 = 82.4 + 2 × 3.3
Then the percentage of students with scores between 75.8 and 89 make up the part of the distribution that lies within 2 standard deviations of the mean. The empirical (68-95-99.7) rule says that approximately 95% of any distribution lies within this range.
Answer:
b
Step-by-step explanation:
A math professor is wondering if students today are better or worse than in the past. He has given the same final to this year's class that he gave ten years ago. Compute mean, median, and mode for both classes and write a paragraph summarizing the differences.
This Year
35 45 65 75 87
80 69 71 53 90
99 95 70 82 73
93 67 61 57 74
72 77 71 81 83
Ten Years Ago
56 77 75 76 59
74 51 89 55 79
67 77 69 91 68
90 65 79 69 79
87 86 98 91 95
Answers
Answer:
Kindly check explanation
Step-by-step explanation:
Given the following data:
This year :
35, 45, 53, 57, 61, 65, 67, 69, 70, 71, 71, 72, 73, 74, 75, 77, 80, 81, 82, 83, 87, 90, 93, 95, 99
Mean = ΣX / n = 1825 / 25 = 73
The mode = 71 ( most frequently occurring)
Median = 1/2(n+1)th term = 1/(26) = 13th term
Median = 73
10 years ago :
51, 55, 56, 59, 65, 67, 68, 69, 69, 74, 75, 76, 77, 77, 79, 79, 79, 86, 87, 89, 90, 91, 91, 95, 98
Mean = ΣX / n = 1902 / 25 = 76.08
The mode = 79 ( most frequently occurring)
Median = 1/2(n+1)th term = 1/(26) = 13th term
Median = 77
According to the computed statistics, we can conclude that, today is worse than the past as the average score which is almost similar to the median value is higher 10 years ago and the modal score is better 10 years ago as well.
NO LINKS OR ANSWERING QUESTIONS YOU DON'T KNOW!!!!
Determine the intervals where the value of f(x) is positive, when f(x)= (x + 7)(2x + 3)(x + 5). Choose all that apply
a. -∞ < x < 7
b. -7 < x < -5
c. -5 < x < -3/2
d. -3/2 < x < ∞
Answers
Answer:
b and dStep-by-step explanation:
Find zero's:
x = -7x = -3/2x = -5The intervals:
x < -7, all negative, the result is negativex is between -7 and -5, two negatives, the result is positivex is between -5 and -3/2, one negative, the result is negativex is greater than -3/2, all 3 positives, the result is positiveAs we see correct choices are b and d
Solve for x. Round to the nearest tenth, if necessary.
S
540
R
2.3
X
O
Please help
Answers
Answer:
[tex]\boxed {\boxed {\sf x \approx 1.9}}[/tex]
Step-by-step explanation:
We are asked to find x, a missing side in a triangle.
This is a right triangle because there is a small square in the corner representing a 90 degree or right angle. Therefore, we can use right triangle trigonometry. The three main functions are:
sinθ= opposite/hypotenuse cosθ= adjacent/hypotenuse tanθ= opposite/adjacentExamine the triangle. We will use angle S, measuring 54 degrees, for theta. Side QR, measuring x, is opposite angle S. Side QS, measuring 2.3, is the hypotenuse because it is opposite the right angle. Since we have the opposite and hypotenuse, we will use sine.
[tex]sin \theta = \frac {opposite}{hypotenuse}[/tex]
θ= 54opposite= x hypotenuse = 2.3[tex]sin (54)= \frac{ x}{2.3}[/tex]
We are solving for x, so we must isolate the variable. It is being divided by 2.3 The inverse operation of division is multiplication, so we multiply both sides by 2.3
[tex]2.3* sin (54)= \frac{x}{2.3}*2.3[/tex]
[tex]2.3* sin (54)=x[/tex]
[tex]2.3*0.8090169944=x[/tex]
[tex]1.860739087 =x[/tex]
Round to the nearest tenth. The 6 in the hundredth place to the right tells us to round the 8 up to a 9.
[tex]1.9 \approx x[/tex]
x is approximately 1.9
Find COS Instructions: Find the value of the trigonometric ratio. Make sure to simplify the If needed
Answers
Answer:
Sin A = 15 / 17
Step-by-step explanation:
Given a right angled triangle, we are to obtain the Sin of the angle A ;
Using trigonometry, the sin of the angle A, Sin A is the ratio of the angle opposite A to the hypotenus of the right angle triangle.
Hence. Sin A = opposite / hypotenus
Opposite = 15 ; hypotenus = 17
Sin A = 15 / 17
(B) An airline knows from experience that the distribution of the number of suitcases that get lost each week on a certain route is normal with μ (mean) = 15.5 and σ (standard deviation) = 3.6. What is the probability that during a given week the airline will lose between 11 and 19 suitcases?
Answers
Answer:
The correct answer is "0.7289".
Step-by-step explanation:
The given values are:
Mean,
[tex]\mu = 15.5[/tex]
Standard deviation,
[tex]\sigma = 3.6[/tex]
As we know,
⇒ [tex]z = \frac{(x - \mu)}{\sigma}[/tex]
The probability will be:
⇒ [tex]P(11< x< 19) = P(\frac{11-15.5}{3.6} <z<\frac{19-15.5}{3.6})[/tex]
[tex]=P(z< 0.9722)-P(z< -1.25)[/tex]
By using the z table, we get
[tex]=0.8345-0.1056[/tex]
[tex]=0.7289[/tex]
The product of x and its opposite is always 1.
O True
O False
Answers
Answer:
False
Step-by-step explanation:
x
The opposite of x is -x
x* -x = -x^2
This is not always 1
Answer:
false
Step-by-step explanation:
x*-x= - x ² so its not always 1
so I just started using brainly sorry if its not appropriate
find the measure of the angle
Answers
Answer: 86
Step-by-step explanation:
This is a cyclic quadilateral in which opposite angles adds upto 180.
Let the unknown angle be x
ATQ
x + 94 = 180
x = 180 - 94
x = 86
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What is the measure of b, in degrees
Answers
Answer:
B) 32
Step-by-step explanation:
(sin 74) / 10 = (sin c) / 10
c = 74
180 - 74 -74
= 32
1. Find the volume of a rectangular block 15 cm long, 5 cm wide and 10 cm length
Answers
9514 1404 393
Answer:
750 cm³
Step-by-step explanation:
The volume is given by the formula ...
V = LWH . . . . where L, W, H represent length, width, height
The volume is the product of the dimensions.
V = (15 cm)(5 cm)(10 cm) = 750 cm³
Last year, Rob set up the Road Runner Race for his school.
The race was 1,200 meters long and 188 people signed up to
run the race. 38 people did not show up to run. This year,
there will be 3 times as many runners as last year. How
many people will run the race this year?
Answers
Answer:
450 runners
Step-by-step explanation:
Charla has six segments with which to make two triangles. The segments lengths are 2 in., 3 in., 4 in., 5 in., 6 in., and 7 in. Which are possible side lengths of her two triangles?
2 in., 4 in., 6 in. and 3 in., 5 in., 7 in.
2 in., 5 in., 6 in. and 3 in., 4 in., 7 in.
2 in., 3 in., 4 in. and 5 in., 6 in., 7 in.
2 in., 3 in., 6 in. and 4 in., 5 in., 7 in.
Answers
Answer:
The answer is option C
2 in., 3 in., 4 in. and 5 in., 6 in., 7 in.
Step-by-step explanation:
Find f(-1) given f(x) = –2x^3 + 3x^2 – 22
Answers
[tex]\\ \sf\longmapsto f(-1)[/tex]
[tex]\\ \sf\longmapsto -2x^3+3x^2-22[/tex]
[tex]\\ \sf\longmapsto -2(-1)^3+3(-1)^2-22[/tex]
[tex]\\ \sf\longmapsto -2(-1)+3(1)-22[/tex]
[tex]\\ \sf\longmapsto 2+3-22[/tex]
[tex]\\ \sf\longmapsto 5-22[/tex]
[tex]\\ \sf\longmapsto -17[/tex]
What is the equation of a horizontal line passing through the point (-7,5)?
Oy = 5
Oy = -7
Ox=5
Ox= - 7
Answers
Answer:
1st option, y = 5
Step-by-step explanation:
when the line is horizontal, it's parallel to the x axis
Answer:
y = 5
Step-by-step explanation:
The equation of a horizontal line parallel to the x- axis is
y = c
where c is the value of the y- coordinates the line passes through
The line passes through (- 7, 5 ) with y- coordinate 5 , then
y = 5 ← is the equation of the line
Determine the maturity value of a 45-day note for $1,250 dated May 23 and bearing interest 8%.
Answers
The maturity value of a 45-day note for $1,250 dated May 23 and bearing interest 8% is $1,262.5
Using this formula
Maturity value=Principal amount+ Interest
Let plug in the formula
Maturity value=$1,250+($1,250*8%*45 days/360 days)
Maturity value=$1,250+$12.5
Maturity value=$1,262.5
Inconclusion the maturity value is $1,262.5
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What is the standard deviation?
8, 10, 12,14,16,18,20
PLEASE show work
Answers
Answer:
4
Step-by-step explanation:
The given data is :
8, 10, 12,14,16,18,20
We need to find the standard deviation. Here,
Count = 7
Sum, Σx: 98
Mean, μ: 14
The standard deviation is given by :
[tex]\sigma=\sqrt{\dfrac{1}{N}\Sigma(x_i-\mu)^2}[/tex]
or
[tex]\sigma^2=\dfrac{1}{N}\Sigma(x_i-\mu)^2\\\\=\dfrac{(8-14)^2+...+(20-14)^2}{7}\\\\=\dfrac{112}{7}\\\\\sigma^2=16\\\\\sigma=4[/tex]
So, the standard deviation of the given data is 4.
A researcher wants to better understand the health benefits of eating vegetables. In a study he finds 300 adults aged 45-60 who eat at least 3 servings of vegetables a day on average. He finds another 200 adults who eat less than 3 servings of vegetables a day on average. The researcher looks at rates of cancer and heart disease in each group and compares both groups. In another study, the researcher finds 500 adults aged 45-60 who eat less than 3 servings of vegetables a day on average, and are willing to participate in a study. The researcher randomly assigns 250 of these adults to a diet which includes 4 servings of vegetables a day. The other 250 continue their usual habits. After 4 years, the rates of cancer and heart disease between the two groups are compared
Identify the statement that correctly states the reason for considering the first study as an observational study and second study as an experiment.
a. In the first study, the treatment is not imposed on the subjects, whereas in the second study the treatment is imposed on the subjects.
b. In the first study, the treatment is not imposed on every subject, whereas in the second study the treatment is imposed on every subject.
c. In the first study, the subjects were not randomly chosen, whereas in the second study the subjects were randomly assigned.
Answers
Answer:
a. In first study, the treatment is not imposed on the subjects, whereas in the second study the treatment is imposed on subjects.
Step-by-step explanation:
In the first study, observation are made on 300 adults who eat 3 servings of vegetables a day on average. The second study has further intensified the research which imposed treatment on the subjects. The random samples of adults are observed in both studies.
What is the mean for the data shown in the line plot?
5 and 7
5
4
8
Answers
Answer:
The mean of the data: 5,7,5,4,8 is 5.8
Step-by-step explanation:
To find the mean, add up the numbers, then divide them by the number of data points. So 5 + 7 + 5 + 4 + 8 = 29, and 29 divided by 5 is 5.8
Which of the following behaviors would best describe someone who is listening and paying attention? a) Leaning toward the speaker O b) Interrupting the speaker to share their opinion c) Avoiding eye contact d) Asking questions to make sure they understand what's being said
Answers
The answer is A and D
good luck
Need helpppp ! tyyy
Answers
Answer:
63°
Step-by-step explanation:
Both angle 3 and 2 are equal because of the property of vertically opposite angles.The average breaking strength of a certain brand of steel cable is 2000 pounds, with a standard deviation of 100 pounds. A sample of 20 cables is selected and tested. Find the sample mean that will cut off the upper 95% of all samples of size 20 taken from the population. Assume the variable is normally distributed.
Answers
Answer:
The sample mean that will cut off the upper 95% of all samples of size 20 taken from the population is of 1963.2 pounds.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
The average breaking strength of a certain brand of steel cable is 2000 pounds, with a standard deviation of 100 pounds.
This means that [tex]\mu = 2000, \sigma = 100[/tex]
A sample of 20 cables is selected and tested.
This means that [tex]n = 20, s = \frac{100}{\sqrt{20}} = 22.361[/tex]
Find the sample mean that will cut off the upper 95% of all samples of size 20 taken from the population.
This is the 100 - 95 = 5th percentile, which is X when Z has a p-value of 0.05, so X when Z = -1.645. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]-1.645 = \frac{X - 2000}{22.361}[/tex]
[tex]X - 2000 = -1.645*22.361[/tex]
[tex]X = 1963.2[/tex]
The sample mean that will cut off the upper 95% of all samples of size 20 taken from the population is of 1963.2 pounds.
Which of the following functions has order 2 rotational symmetry about the same origin?
Answers
The answer is "Option B", and the further explanation can be defined as follows:
A rectangle is symmetrical in 2 ways. In particular, it has two-order rotational symmetry (RS2).If an object rotates 360 degrees, it's an ordering of symmetrical is the number of times it appears to be the same.There are three levels of matching: Order 2 if only two times, Order 3 if three matches are made, and so forth.The wrong choice can be defined as follows:
In option a and c, both are wrong because it has no rotational symmetry.In option d, it is wrong because it downs the diagram on the negative (x,y) axis.Therefore, "Option B" is correct and its diagram is defined in the attached file.
Learn more:
2 rotational symmetry: brainly.com/question/1531736
The Rogers family and the Brooks family each used their sprinklers last summer. The Rogers family's sprinkler was used for 30 hours. The Brooks family's sprinkler was used for 25 hours. There was a combined total output of 1775 L of water. What was the water output rate for each sprinkler if the sum of the two rates was 65 L per hour?
Answers
Step-by-step explanation:
what happens if there is excess or deficit of proteins in our body
Imagine that you are given two linear equations in slope-intercept form. You
notice that both the slopes and the y-intercepts are the same. How many
solutions would you expect for this system of equations?
O A. 1
ОВ. о
C. infinitely many
O D. cannot be determined
SURAT
Answers
Answer:
C. infinitely many
Step-by-step explanation:
If two equations in slope-intercept form have the same slope and y-intercept they must be the same line. Additionally, the solutions of a system of equations are wherever the two lines intersect. Since the lines are the same they must intersect at every point. Therefore, there are infinitely many solutions.
