Answer:
[tex]z=\frac{31.1-31.3}{\frac{1.3}{\sqrt{140}}}=-1.82[/tex]
The p value for this case would be given by:
[tex]p_v =2*P(z<-1.82)=0.0688[/tex]
For this case since the p value is higher than the significance level we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 31.3 MPG
Step-by-step explanation:
Information given
[tex]\bar X=31.1[/tex] represent the sample mean
[tex]\sigma=1.3[/tex] represent the population standard deviation
[tex]n=140[/tex] sample size
[tex]\mu_o =31.3[/tex] represent the value that we want to test
[tex]\alpha=0.02[/tex] represent the significance level for the hypothesis test.
z would represent the statistic
[tex]p_v[/tex] represent the p value
Hypothesis to test
We want to test if the true mean is equal to 31.3 MPG, the system of hypothesis would be:
Null hypothesis:[tex]\mu =31.3[/tex]
Alternative hypothesis:[tex]\mu \neq 31.3[/tex]
Since we know the population deviation, the statistic is given by
[tex]z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}[/tex] (1)
Replacing we got:
[tex]z=\frac{31.1-31.3}{\frac{1.3}{\sqrt{140}}}=-1.82[/tex]
The p value for this case would be given by:
[tex]p_v =2*P(z<-1.82)=0.0688[/tex]
For this case since the p value is higher than the significance level we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 31.3 MPG
A regular octagon has what type of symmetry?
A.
line symmetry only
B.
point symmetry only
C.
both point and line symmetry
OD.
neither point nor line symmetry
Answer:
C
Step-by-step explanation:
A regular octagon has 8 lines of symmetry.
The point of intersection of the lines of symmetry of a regular octagon is the point of symmetry.
A regular octagon has both point and line symmetry. Thus, option C is the right choice.
What are the different types of symmetry?The different types of symmetry are:
Line symmetry: A shape is symmetric about a line when the two images formed on the two sides of the line are identical.Point symmetry: A shape is symmetric about a point, when the shape is rotated about the point for 180°, gives the same shape.Rotational symmetry: A shape is rotationally symmetric, when the shape on rotation about a point, with an angle of value less than 360°, gives the same shape back.How to solve the given question?In the question, we are asked about the types of symmetry that a regular octagon has.
A regular octagon has 8 lines of symmetry about which the shape divides itself into equal halves.
These are the 4 lines joining each opposite vertex, and the other 4 are the lines passing through the midpoints of opposite sides.
A regular octagon is point symmetric as 180° rotation about the point of intersection of the lines of symmetry gives the same shape back.
Thus, we can say that a regular octagon has both point and line symmetry. Thus, option C is the right choice.
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How many units of insulin are in 0.75 ML a regular U – 100 insulin
Answer:
0.75 ML of insulin contains 75 units of insulin
Step-by-step explanation:
U - 100 insulin hold 100 units of insulin per ml
This means that:
1 ML = 100 units
∴ 0.75 ML = 100 × 0.75 = 75 units
Therefore 0.75 ML of insulin contains 75 units of insulin
Which graph shows a function whose domain and range exclude exactly one value?
Answer:
C (the third graph)
Step-by-step explanation:
This graph's function has a domain and range that both exclude one value, which is 0. The x and y values are never 0 in the function, as it approaches 0 but never meets it.
Answer:
see below
Step-by-step explanation:
This graph has an asymptote at y = 0 and x=0
This excludes these values
The domain excludes x =0
The range excludes y=0
A data set is shown in the table. The line of best fit modeling the data is y = 2.69x – 7.95.
Answer:
It’s 0.12
Step-by-step explanation:
Took test
Find the volume of the cone.
4 cm
3 cm
V = [?] cm3
Round to the nearest tenth.
Answer:
Volume of a cone = 1/3πr²h
h = height
r = radius
r = 3cm h = 4cm
Volume = 1/3π(3)²(4)
= 36 × 1/3π
= 12π
= 36.69cm³
= 37cm³ to the nearest tenth
Hope this helps
Answer:
37.7
_______
NOT 37
Step-by-step explanation:
v = [tex]\frac{1}{3}[/tex] · [tex]\pi[/tex] · [tex]r^{2}[/tex] · [tex]h[/tex]
v = [tex]\frac{1}{3}[/tex] · [tex]\pi[/tex] · [tex]3^{2}[/tex] · [tex]4 = 12\pi = 37.69911 =[/tex] 37.7
HURRY TIMEDD!!!!!
What is the value of the discriminant, b2 − 4ac, for the quadratic equation 0 = x2 − 4x + 5, and what does it mean about the number of real solutions the equation has? The discriminant is −4, so the equation has 2 real solutions. The discriminant is −4, so the equation has no real solutions. The discriminant is 35, so the equation has 2 real solutions. The discriminant is 35, so the equation has no real solutions.
Answer:
Second option is the correct choice.
Step-by-step explanation:
"The discriminant is −4, so the equation has no real solutions."
[tex]x^2-4x+5=0\\\\a=1,\:b=-4,\:c=5:\\\\b^2-4ac=\left(-4\right)^2-4\cdot \:1\cdot \:5=-4[/tex]
Best Regards!
Answer: B
The discriminant is −4, so the equation has no real solutions.
Step-by-step explanation:
Just took quiz EDG2021
Mark Brainliest
A complex electronic system is built with a certain number of backup components in its subsystems. One subsystem has eight identical components, each with a probability of 0.45 of failing in less than 1,000 hours. The sub system will operate if any four of the eight components are operating. Assume that the components operate independently. (Round your answers to four decimal places.)
Required:
Find the probability that the subsystem operates longer than 1000 hours.
Answer:
0.7396 = 73.96% probability that the subsystem operates longer than 1000 hours.
Step-by-step explanation:
For each component, there are only two possible outcomes. Either they fail in less than 1000 hours, or they do not. The components operate independently. So we use the binomial probability distribution 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.
Eight components:
This means that [tex]n = 8[/tex]
Probability of 0.45 of failing in less than 1,000 hours.
So 1 - 0.45 = 0.55 probability of working for longer than 1000 hours, which means that [tex]p = 0.55[/tex]
Find the probability that the subsystem operates longer than 1000 hours.
We need at least four of the components operating. So
[tex]P(X \geq 4) = P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 4) = C_{8,4}.(0.55)^{4}.(0.45)^{4} = 0.2627[/tex]
[tex]P(X = 5) = C_{8,5}.(0.55)^{5}.(0.45)^{3} = 0.2568[/tex]
[tex]P(X = 6) = C_{8,6}.(0.55)^{6}.(0.45)^{2} = 0.1569[/tex]
[tex]P(X = 7) = C_{8,7}.(0.55)^{7}.(0.45)^{1} = 0.0548[/tex]
[tex]P(X = 8) = C_{8,8}.(0.55)^{8}.(0.45)^{0} = 0.0084[/tex]
[tex]P(X \geq 4) = P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8) = 0.2627 + 0.2568 + 0.1569 + 0.0548 + 0.0084 = 0.7396[/tex]
0.7396 = 73.96% probability that the subsystem operates longer than 1000 hours.
What is the midpoint of the line segment with endpoints (1,-6) and (-3,4)?
O A. (-1,-1)
O B. (-2,-2)
O C. (-1,-2)
OD. (-2,-1)
please help
Answer:
(-1,-1)
Step-by-step explanation:
To find the x coordinate of the midpoint, add the x coordinates of the endpoint and divide by 2
(1+-3)/2 = -2/2 = -1
To find the y coordinate of the midpoint, add the y coordinates of the endpoint and divide by 2
(-6+4)/2 = -2/2 = -1
(-1,-1)
Is (1,2), (2,3) (3,4), (4,5) a function?
Answer:
yes
Step-by-step explanation:
The domain is the set of x-values: {1, 2, 3, 4}. None of these are repeated, so this relation is a function.
What is the general form of the equation of the line shown? 2 x - y + 3 = 0 2 x - y - 3 = 0 x - 2 y - 3 = 0
Answer:
2x - y - 3 = 0
Step-by-step explanation:
Find slope-intercept form first: y = mx + b
Step 1: Pick out 2 points
In this case, I picked out (2, 1) and (0, -3) from the graph
Step 2: Using slope formula y2 - y1/x2 - x1 to find slope
-3 - 1/0 - 2
m = 2
Step 3: Place slope formula results into point-slope form
y = 2x + b
Step 4: Plug in a point to find b
-3 = 2(0) + b
b = -3
Step 5: Write slope-intercept form
y = 2x - 3
Step 6: Move all variables and constants to one side
0 = 2x - 3 - y
Step 7: Rearrange
2x - y - 3 = 0 is your answer
What is AB? Geometry help please
Answer:
AB = 37 units.
Step-by-step explanation:
Solve for AB using the Pythagorean theorem:
c² = a² + b² (c being AB in this instance)
Plug in the values of the legs of the triangle:
c² = 12² + 35²
c² = 144 + 1225
c² = 1369
c = √1369
c = 37
Therefore, AB = 37.
13. Two points P and Q, 10 m apart on level ground,
are due West of the foot B of a tree TB. Given that
TPB = 23° and TQB = 32°, find the height of tree
Answer: height = 13.24 m
Step-by-step explanation:
Draw a picture (see image below), then set up the proportions to find the length of QB. Then input QB into either of the equations to find h.
Given: PQ = 10
∠TPB = 23°
∠TQB = 32°
[tex]\tan P=\dfrac{opposite}{adjacent}\qquad \qquad \tan Q=\dfrac{opposite}{adjacent}\\\\\\\tan 23^o=\dfrac{h}{10+x}\qquad \qquad \tan 32^o=\dfrac{h}{x}\\\\\\\underline{\text{Solve each equation for h:}}\\\tan 23^o(10+x)=h\qquad \qquad \tan 32^o(x)=h\\\\\\\underline{\text{Set the equations equal to each other and solve for x:}}\\\tan23^o(10+x)=\tan32^o(x)\\0.4245(10+x)=0.6249x\\4.245+0.4245x=0.6249x\\4.245=0.2004x\\21.18=x[/tex]
[tex]\underline{\text{In put x = 21.18 into either equation and solve for h:}}\\h=\tan 32^o(x)\\h=0.6249(2.118)\\\large\boxed{h=13.24}[/tex]
An article reports that 1 in 500 people carry the defective gene that causes inherited colon cancer. In a sample of 2000 individuals, what is the approximate distribution of the number who carry this gene
Answer:
Brianliest!
Step-by-step explanation:
4
1 in 500
500 x 4 = 2000
4 in 2000
a) find the value of 2x+y wehn x =4 and y =3 b) find the value of a^2 + b when a = -2 and b = 5
Answer:
a. 11b. 9Solution,
a. Given,
X=4
y=3
Now,
[tex]2x + y \\ = 2 \times 4 + 3 \\ = 8 + 3 \\ = 11[/tex]
b. Given,
a=-2
b=5
Now,
[tex] {a}^{2} + b \\ = {( - 2)}^{2} + 5 \\ = 4 + 5 \\ = 9[/tex]
hope this helps...
Good luck on your assignment..
A line passes through the points P(1,-6,7) and Q(-9,10,-5) find the standard parametric equations for the line, written using the base point P(1,-6,7) and the components of the vector PQ rightarrow.
x = _________, y = _________, z = __________.
Answer:
[tex]x = 1-10t\\y = -6+16t\\z = 7-12t[/tex]
Step-by-step explanation:
We are given the coordinates of points P(1,-6,7) and Q(-9,10,-5).
The values in the form of ([tex]x,y,z[/tex]) are:
[tex]x_1=1\\x_2=-9\\y_1=-6\\,y_2=10\\z_1=7\\z_2=-5[/tex]
[tex]$\vec{PQ}$[/tex] can be written as the difference of values of x, y and z axis of the two points i.e. change in axis.
[tex]\vec{PQ}=<x_2-x_1,y_2-y_1,z_2-z_1>[/tex]
[tex]\vec{PQ} = <(-9-1), 10-(-6),(-5-7)>\\\Rightarrow \vec{PQ} = <-10, 16,-12>[/tex]
The equation of line in vector form can be written as:
[tex]\vec{r} (t) = <1,-6,7> + t<-10,16,-12>[/tex]
The standard parametric equation can be written as:
[tex]x = 1-10t\\y = -6+16t\\z = 7-12t[/tex]
Which of these fractions is an improper fraction? 5/3 or 3/5
Answer:
5/3 is an improper fraction because 5 is higher then 3. So the correct way of writing it would be 1 2/3.
Step-by-step explanation:
What is the relative change from 6546 to 4392
Answer:
The relative change from 6546 and 4392 is 49.04
Step-by-step explanation:
What is the volume of this container?
Step-by-step explanation:
Concepto 20 pies, 20´ × 8´ × 8´6" 40 pies High Cube, 40´ × 8´ × 9´ 6"
Ancho 2352 mm / 7´9" 2352 mm / 7´9"
Altura 2393 mm / 7´10" 2698 mm / 8´10"
Capacidad 33,2 m³ / 1172 ft³ 76, m³ / 2700 ft³
ESPERO QUE TE AYUDE :D
In a sample of 22 people, the average cost of a cup of coffee is $2.70. Assume the population standard deviation is $0.93. What is the 90% confidence interval for the cost of a cup of coffee
Answer:
$2.70+/-$0.33
= ( $2.37, $3.03)
Therefore, the 90% confidence interval (a,b) = ( $2.37, $3.03)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = $2.70
Standard deviation r = $0.93
Number of samples n = 22
Confidence interval = 90%
z(at 90% confidence) = 1.645
Substituting the values we have;
$2.70+/-1.645($0.93/√22)
$2.70+/-1.645($0.198276666210)
$2.70+/-$0.326165115916
$2.70+/-$0.33
= ( $2.37, $3.03)
Therefore, the 90% confidence interval (a,b) = ( $2.37, $3.03)
If the radius of a circle is 31.2 cm, what is the approximate area if you use 3.14 for pi and the area is rounded to the nearest tenth?
Answer:
3056.6 cm^2
Step-by-step explanation:
A = (pi)r^2 = 3.14 * 31.2 cm * 31.2 cm = 3056.6 cm^2
Answer: 3056.60 sq. cm.
Step-by-step explanation:
Area of a circle = π x r^2
= 3.14 x 31.2^2
= 3056.60
If Line segment C B. bisects ∠ACD, what additional information could be used to prove ΔABC ≅ ΔDBC using SAS? Select three options.
m∠ABC = 125° and AB ≅ DB
ΔACD is isosceles with base AD
ΔABD is isosceles with base AD
CD = 52 cm
AB = 29 cm
Answer:
Option (1)
Step-by-step explanation:
In the figure attached,
BC is the angle bisector of angle ACD.
To prove ΔABC and ΔDBC congruent by SAS property we require two sides and the angle between these sides to be congruent.
Since BC ≅ BC [Reflexive property]
∠ABC ≅ ∠CBD ≅ 125°
And sides AB ≅ BD
Both the triangles will be congruent.
Therefore, additional information required to prove ΔABC ≅ ΔDBC have been given in option (1).
Therefore, Option (1) will be the answer.
The additional information that could be used to prove ΔABC ≅ ΔDBC
using SAS are;
m∠ABC = 125° and [tex]\overline{AB}[/tex] ≅ [tex]\overline{DB}[/tex] ΔACD is isosceles, with base [tex]\overline{AD}[/tex][tex]\overline{CD}[/tex] = 52 cmReasons:
The given information are;
[tex]\overline{CB}[/tex] bisects ∠ACD
The given information from the diagram are;
[tex]\overline{AC}[/tex] = 52 cm
[tex]\overline{BD}[/tex] = 29 cm
∠CBD = 125°
Solution;
First selected option; m∠ABC = 125° and [tex]\overline{AB}[/tex] ≅ [tex]\overline{DB}[/tex]
m∠ABC = 125° and [tex]\overline{AB}[/tex] ≅ [tex]\overline{DB}[/tex][tex]\overline{CB}[/tex] ≅ [tex]\overline{CB}[/tex] (reflexive property)
ΔABC ≅ ΔDBC (SAS rule of congruency)
Second selected option; ΔACD is isosceles, with base [tex]\overline{AD}[/tex]
∠ACB ≅ ∠DCB (definition of angle bisector)
ΔACD is isosceles, with base [tex]\overline{AD}[/tex] (Additional information)[tex]\overline{CD}[/tex] ≅ [tex]\overline{AC}[/tex] (definition of isosceles triangle)
[tex]\overline{CB}[/tex] ≅ [tex]\overline{CB}[/tex] (reflexive property)
ΔABC ≅ ΔDBC (SAS rule of congruency)
Third selected option; [tex]\overline{CD}[/tex] = 52 cm
∠ACB ≅ ∠DCB (definition of angle bisector)
[tex]\overline{CD}[/tex] = 52 cm = [tex]\overline{AC}[/tex] (given) (additional information)[tex]\overline{CD}[/tex] ≅ [tex]\overline{AC}[/tex] (definition of congruency)
[tex]\overline{CB}[/tex] ≅ [tex]\overline{CB}[/tex] (reflexive property)
ΔABC ≅ ΔDBC (SAS rule of congruency)
The Side-Angle-Side, SAS, rule of congruency states that two triangles are
congruent if two sides and an included angle of one triangle are
congruent to the corresponding two sides and included angle on the other
triangle.
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for a sample size of 115 and a population parameter of 0.1,what is the standard deviation of the normal curve that can be used to approximate the binomial probability histogram. Round your answer to three decimal places
A.0.028
B.0.054
C.0.043
D.0.035
Answer:
A) 0.028
Step-by-step explanation:
Given:
Sample size, n = 115
Population parameter, p = 0.1
The X-Bin(n=155, p=0.1)
Required:
Find the standard deviation of the normal curve that can be used to approximate the binomial probability histogram.
To find the standard deviation, use the formula below:
[tex]\sigma = \sqrt{\frac{p(1-p)}{n}}[/tex]
Substitute figures in the equation:
[tex]\sigma = \sqrt{\frac{0.1(1 - 0.1)}{115}}[/tex]
[tex]\sigma = \sqrt{\frac{0.1 * 0.9}{115}}[/tex]
[tex]\sigma = \sqrt{\frac{0.09}{115}}[/tex]
[tex] \sigma = \sqrt{7.826*10^-^4}[/tex]
[tex] \sigma = 0.028 [/tex]
The Standard deviation of the normal curve that can be used to approximate the binomial probability histogram is 0.028
√x+3 = √5x-1 Find the value of X
Answer:
x=1
Step-by-step explanation:
sqrt(x+3) = sqrt(5x-1)
Square each side
x+3 = 5x-1
Subtract x from each side
3 = 4x-1
Add 1 to each side
4 =4x
Divide by 4
x=1
Answer:
x= 1
Step-by-step explanation:
[tex]\sqrt{x+3}=\sqrt{5x-1}[/tex]
Square both sides.
x + 3 = 5x - 1
Subtract 3 and 5x on both sides.
x - 5x = -1 - 3
-4x = -4
Divide -4 into both sides.
-4x/-4 = -4/-4
x = 1
The makers of a soft drink want to identify the average age of its consumers. A sample of 25 consumers was taken. The average age in the sample was 31 years with a standard deviation of 3.8 years.The Margin of error of the 99% confidence interval for the average age of the consumers is a.1.90 years b.2.13 years c.4.10 years d.1.65 years
Answer:
a.1.90 years
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1-0.99}{2} = 0.005[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].
So it is z with a pvalue of [tex]1-0.005 = 0.995[/tex], so [tex]z = 2.575[/tex]
Now, find the margin of error M as such
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
In this question:
[tex]n = 25, \sigma = 3.8[/tex]
So
[tex]M = 2.575*\frac{3.8}{\sqrt{25}} = 1.90[/tex]
So the correct answer is:
a.1.90 years
What is the algebraic expression for "the sum of three times a number and seven"? A. 3 x + 7 B. 3 x + 11 x C. 3 + 7 x
Answer:
3x+7
Step-by-step explanation:
Three times a number, let x be the number and 7 so plus 7
The algebraic expression for the given phrase is 3x+7. Therefore, the correct answer is option A.
The given phrase is "the sum of three times a number and seven".
Variables and constants are combined to generate algebraic expressions using a variety of techniques. Terms comprise expressions. A term is the sum of several elements. Both numerical and algebraic (literal) factors are acceptable.
Let the unknown number be x.
Three times of a number = 3x
The number 7 is added to the obtained sum.
That is, 3x+7
So, the expression is 3x+7
The algebraic expression for the given phrase is 3x+7. Therefore, the correct answer is option A.
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If the terms of a polynomial do not have a GCF, does that mean it is not factorable?
Can someone please explain how to do this problem? The websites instructions are very poor. Rewrite [tex]\frac{2}{x^{2} -x-12}[/tex] and [tex]\frac{1}{x^{2}-16 }[/tex] as equivalent rational expressions with the lowest common denominator.
Answer: x = -5
Step-by-step explanation:
If you factor each denominator, you can find the LCM.
[tex]\dfrac{2}{x^2-x-12}=\dfrac{1}{x^2-16}\\\\\\\dfrac{2}{(x-4)(x+3)}=\dfrac{1}{(x-4)(x+4)}\\\\\\\text{The LCM is (x-4)(x+4)(x+3)}\\\\\\\dfrac{2}{(x-4)(x+3)}\bigg(\dfrac{x+4}{x+4}\bigg)=\dfrac{1}{(x-4)(x+4)}\bigg(\dfrac{x+3}{x+3}\bigg)\\\\\\\dfrac{2(x+4)}{(x-4)(x+4)(x+3)}=\dfrac{1(x+3)}{(x-4)(x+4)(x+3)}\\[/tex]
Now that the denominators are equal, we can clear the denominator and set the numerators equal to each other.
2(x + 4) = 1(x + 3)
2x + 8 = x + 3
x + 8 = 3
x = -5
Can someone help me with this please
Answer:
21
Step-by-step explanation:
so this is the way i learned it
compare side to side so CA is 12 and LM is 9 so its 4/3
CB is 8 LN is 6 so its 4/3
so AB is 8 so MN would have to be 4/3 which would made MN 6 so MNL would be 21
Answer:
21
Step-by-step explanation:
ΔLMN ≅ ΔABC with a scale factor of 0.75
If Line AB is similar to Line MN, then Line MN is 6.
Perimeter of ΔLMN
9+6+6=
15+6=
21
how many dimes equal $12.60? (show your work)
Answer:
126
Step-by-step explanation:
0.1x=12.6
126
A fence 6 feet tall runs parallel to a tall building at a distance of 6 feet from the building. We want to find the the length of the shortest ladder that will reach from the ground over the fence to the wall of the building. Here are some hints for finding a solution: Use the angle that the ladder makes with the ground to define the position of the ladder and draw a picture of the ladder leaning against the wall of the building and just touching the top of the fence. If the ladder makes an angle 0.82 radians with the ground, touches the top of the fence and just reaches the wall, calculate the distance along the ladder from the ground to the top of the fence. equation editorEquation Editor The distance along the ladder from the top of the fence to the wall is equation editorEquation Editor Using these hints write a function L(x) which gives the total length of a ladder which touches the ground at an angle x, touches the top of the fence and just reaches the wall. L(x) = equation editorEquation Editor . Use this function to find the length of the shortest ladder which will clear the fence. The length of the shortest ladder is equation editorEquation Editor feet.
Answer:
12√2 feet ≈ 16.97 feet
Step-by-step explanation:
For the dimensions shown in the attached diagram, the distance "a" along the ladder from the ground to the fence is ...
a = (6 ft)/sin(x) = (6 ft)/sin(0.82) ≈ 8.206 ft
The distance along the ladder from the top of the fence to the wall is ...
b = (6 ft)/cos(x) = (6 ft)/cos(0.82) ≈ 8.795 ft
__
In general, the distance along the ladder from the ground to the wall is ...
L(x) = a +b
L(x) = 6/sin(x) +6/cos(x)
This distance will be shortest for the case where the derivative with respect to x is zero.
L'(x) = 6(-cos(x)/sin(x)² +sin(x)/cos(x)²) = 6(sin(x)³ -cos(x)³)/(sin(x)²cos(x²))
This will be zero when the numerator is zero:
0 = 6(sin(x) -cos(x))(1 -sin(x)cos(x))
The last factor is always positive, so the solution here is ...
sin(x) = cos(x) ⇒ x = π/4
And the length of the shortest ladder is ...
L(π/4) = 6√2 + 6√2
L(π/4) = 12√2 . . . . feet
_____
The ladder length for the "trial" angle of 0.82 radians was ...
8.206 +8.795 = 17.001 . . . ft
The actual shortest ladder is ...
12√2 = 16.971 . . . feet