The graph of -4x +3y-5= 0 passes through two points, A(2a, -1) and B(4,b). What is the value of a-b?
Answers
Answer:
-8
Step-by-step explanation:
The steps are in the photo I attatched
Related Questions
(I’ll give points + brainalist for the correct answer with an explanation)
Answers
Answer:
b
Step-by-step explanation:
divide 1/4 by 20
Question #3 show steps or how you know
Answers
Answer: Choice D)
(-1.5, -1) and (0, 1)
=============================================================
Explanation:
Exponents can be a bit clunky if you have too many of them, and if they're nested like this. Writing something like e^(x^2) may seem confusing if you aren't careful. I'm going to use a different notation approach. I'll use "exp" notation instead.
So instead of writing something like e^(x^2), I'll write exp(x^2).
The given derivative is
f ' (x) = exp(x^4-2x^2+1) - 2
and this only applies when -1.5 < x < 1.5
Apply the derivative to both sides and we'll find the second derivative
f ' (x) = exp(x^4-2x^2+1) - 2
f '' (x) = d/dx[ exp(x^4-2x^2+1) - 2 ]
f '' (x) = exp(x^4-2x^2+1)*d/dx[ x^4-2x^2+1 ]
f '' (x) = exp(x^4-2x^2+1)*(4x^3-4x)
f '' (x) = (4x^3-4x)*exp(x^4-2x^2+1)
From here, we need to find the roots of f '' (x).
Set f '' (x) equal to zero and solve to get...
f '' (x) = 0
(4x^3-4x)*exp(x^4-2x^2+1) = 0
4x^3-4x = 0 ..... or .... exp(x^4-2x^2+1) = 0
4x(x^2-1) = 0
4x(x+1)(x-1) = 0
4x = 0 or x+1 = 0 or x-1 = 0
x = 0 or x = -1 or x = 1
Those are the three roots. We ignore the equation exp(x^4-2x^2+1) = 0 because it doesn't have any real number solutions.
---------------------
The three roots of x = 0 or x = -1 or x = 1 represent possible locations of points of inflection (POI). Recall that a POI is where the function changes concavity. To determine if we have a POI or not, we'll need to a sign test.
Draw out a number line. Plot -1, 0, and 1 in that order on it. Pick something to the left of -1 but larger than -1.5, lets say we pick x = -1.2. Plugging this into the second derivative function leads to...
f '' (x) = (4x^3-4x)*exp(x^4-2x^2+1)
f '' (-1.2) = (4(-1.2)^3-4(-1.2))*exp((-1.2)^4-2(-1.2)^2+1)
f '' (-1.2) = -2.563
That value is approximate. The actual value itself doesn't matter. What does matter is the sign of the result. The negative second derivative value tells us we have a concave down region. So we just found that f(x) is concave down for the interval -1.5 < x < -1, which converts to the interval notation (-1.5, -1)
Repeat the process for something between x = -1 and x = 0. I'll pick x = -0.5 and it leads to f '' (-0.5) = 2.63 approximately. The positive result tells us that we have a concave up region. Therefore, -1 < x < 0 is not part of the answer we're after.
Repeat for something between x = 0 and x = 1. I'll pick x = 0.5 and it produces f '' (0.5) = -2.63 approximately. So the region 0 < x < 1 is also concave down. Meaning that the interval notation (0,1) is also part of the answer.
So far we have the interval notation of (-1.5, -1) and (0,1) as part of our solution set.
Lastly, we need to check something to the right of x = 1, but smaller than 1.5; let's go for x = 1.2
You should find that f '' (1.2) = 2.563 which allows us to rule out the region on the interval 1 < x < 1.5
Overall, the final answer is (-1.5, -1) and (0, 1)
An article in The Engineer (Redesign for Suspect Wiring," June 1990) reported the results of an investigation into wiring errors on commercial transport aircraft that may produce faulty information to the flight crew. Such a wiring error may have been responsible for the crash Of a British Midland Airways aircraft in January 1989 by causing the pilot to shut down the wrong engine. Of 1600 randomly selected aircraft, eight were found to have wiring errors that could display incorrect information to the flight crew.
Required:
a. Find a 99% confidence interval on the proportion of aircraft that have such wiring errors. Round your answers to 4 decimal places.
b. Suppose we use the information in this example to provide a preliminary estimate of p. How large a sample would be required to produce an estimate of p that we are 99% confident differs from the true value by at most 0.009?
c. Suppose we did not have a preliminary estimate of p. How large a sample would be required if we wanted to be at least 99% confident that the sample proportion differs from the true proportion by at most 0.009 regardless of the true value of p?
Answers
Answer:
a) The 99% confidence interval on the proportion of aircraft that have such wiring errors is (0.0005, 0.0095).
b) A sample of 408 is required.
c) A sample of 20465 is required.
Step-by-step explanation:
Question a:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
Of 1600 randomly selected aircraft, eight were found to have wiring errors that could display incorrect information to the flight crew.
This means that [tex]n = 1600, \pi = \frac{8}{1600} = 0.005[/tex]
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.005 - 2.575\sqrt{\frac{0.005*0.995}{1600}} = 0.0005[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.005 + 2.575\sqrt{\frac{0.005*0.995}{1600}} = 0.0095[/tex]
The 99% confidence interval on the proportion of aircraft that have such wiring errors is (0.0005, 0.0095).
b. Suppose we use the information in this example to provide a preliminary estimate of p. How large a sample would be required to produce an estimate of p that we are 99% confident differs from the true value by at most 0.009?
The margin of error is of:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
A sample of n is required, and n is found for M = 0.009. So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.009 = 2.575\sqrt{\frac{0.005*0.995}{n}}[/tex]
[tex]0.009\sqrt{n} = 2.575\sqrt{0.005*0.995}[/tex]
[tex]\sqrt{n} = \frac{2.575\sqrt{0.005*0.995}}{0.009}[/tex]
[tex](\sqrt{n})^2 = (\frac{2.575\sqrt{0.005*0.995}}{0.009})^2[/tex]
[tex]n = 407.3[/tex]
Rounding up:
A sample of 408 is required.
c. Suppose we did not have a preliminary estimate of p. How large a sample would be required if we wanted to be at least 99% confident that the sample proportion differs from the true proportion by at most 0.009 regardless of the true value of p?
Since we have no estimate, we use [tex]\pi = 0.5[/tex]
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.009 = 2.575\sqrt{\frac{0.5*0.5}{n}}[/tex]
[tex]0.009\sqrt{n} = 2.575*0.5[/tex]
[tex]\sqrt{n} = \frac{2.575*0.5}{0.009}[/tex]
[tex](\sqrt{n})^2 = (\frac{2.575*0.5}{0.009})^2[/tex]
[tex]n = 20464.9[/tex]
Rounding up:
A sample of 20465 is required.
A rental car company charges $33 per day to rent a car and $0.12 for every
mile driven. Zachary wants to rent a car, knowing that:
• He plans to drive 400 miles.
• He has at most $180 to spend.
Use the drop-down menu below to write an inequality representing d, the
total number of days Zachary can rent the car while staying within his budget.
d
Answers
Answer:
2 days
Step-by-step explanation:
0.12x 400=48.00+33.00=81×2=162.00 for 2 days
18
Type the correct answer in each box. Use numerals Instead of words. If necessary, use / for the fraction bar(s).
The grades received by 200 students follow a normal distribution. The mean of the grades is 70%, and the standard deviation is 7%.
The number of students who received a grade greater than 70% is about
. and the number of students who got a grade higher than
84% is about
Reset
Next
Answers
Answer: 100
5
Step-by-step explanation:
a) The mean of a normal distribution is also the median. Half the population will have values above the mean. Half of 200 is 100, so ...
... 100 students will have grades above 70%.
b) 84% is 14% above the mean. Each 7% is 1 standard deviation, so 14% is 2 standard deviations above the mean. The empirical rule tells you 95% of the population is within 2 standard deviations of the mean, so about 5% of students (10 students) got grades higher than 84% or lower than 56%. The normal distribution is symmetrical, so we expect about 5 students in each range.
... about 5 students will have grades above 84%.
Help 100 points to answer the page
Answers
Answer:
Use trigonometry
sine = opposite leg / hypotenusecosine = adjacent leg / hypotenusetangent = opposite leg / adjacent leg#123/x = sin 68x = 23 / sin 68x = 24.8Choice A
#221/x = tan 26x = 21/ tan 26x = 43.1Choice D
Note. All numbers below are rounded to the nearest tenth#312/x = sin 53x = 12 / sin 53x = 15.0#48/x = tan 34x = 8/tan 34x = 11.9#5x/ 12 = cos 26x = 12 cos 26 x = 10.8#6x / 13 = sin 34x = 13 sin 34x = 7.3#7x / 18 = sin 53x = 18 sin 53 x = 14.4#8x / 10 = tan 30x = 10 tan 30 x = 5.8#9cos X = 21/35 = 3/5#10tan X = 32/24 = 4/3Answer:
the person above me is correct i said that because i did the math and solved it
Step-by-step explanation:
In a certain year, 88% of all Caucasians in the U.S., 73% of all African-Americans, 73% of all Hispanics, and 75% of residents not classified into one of these groups used the Internet for e-mail. At that time, the U.S. population was 64% Caucasian, 11% African-American, and 13% Hispanic. What percentage of U.S. residents who used the Internet for e-mail were Hispanic
Answers
Answer:
The total percentage of U.S. residents who used the Internet for e-mail were Hispanic was 9.5%
Step-by-step explanation:
Given
In a certain year the % share of American population that was Hispanic was 13%
Out of these 13%, 73% Hispanic used the internet for emails.
Now the total percentage of U.S. residents who used the Internet for e-mail were Hispanic was 0.13 * 0.73 = 0.095 = 9.5%
Which of the following is a solution to the equation sin (x) + 2 = 1
Answers
Answer:
-1
Step-by-step explanation:
A man had 15 crates of apples. Each crate had the same number of apples. He sold 70 apples on Monday and twice as many apples on Tuesday. He had 90 apples left. How many apples were there in each crate at first?
Answers
Answer:
=20 apples
Step-by-step explanation:
90+70+140=300
300 crates in total
300÷15=20
If the standard deviation of a data set were originally 4, and if each value in
the data set were multiplied by 1.75, what would be the standard deviation of
the resulting data?
A. 3
B. 4
c. 7
D. 1
Please help
Answers
Answer:
it's a.
Step-by-step explanation:
you have to find the mean
Solve for all values of x by factoring.'
x2 + 10x + 21 = 0
Answers
Answer:
Step-by-step explanation:
2x+10x=12x
12x=-21
x=-1.75
Answer:
x=-7,-3
Step-by-step explanation:
x2+10x+21
(x+7)(x+3)
x=-7,-3
Estimate the sum of 1,256, 379 and 305,986 by first rounding each number to the nearest ten thousand.
Answers
9514 1404 393
Answer:
1,570,000
Step-by-step explanation:
The sum is approximately ...
1,260,000 +310,000 = 1,570,000
_____
Additional comment
It is a good idea to estimate the error associated with an estimate. Here, both numbers are rounded up by about 4000 each, so the estimate is around 8000 high.
12. If one line passes through the points
(-3,8) & (1,9), and a perpendicular line passes
through the point (-2,4), what is another point
that would lie on the 2nd line. Select all that apply.
A. (-1,0)
B. (2,5)
C. (5,2)
D. (-6,3)
E. (8,-3)
F. (-3,8)
Answers
9514 1404 393
Answer:
A, F
Step-by-step explanation:
Points A(-1, 0) and F(-3, 8) lie on the 2nd line. (Its equation is 4x+y=-4.)
ANSWER QUICK
1. Give the value of y.
3y = 51
2. Give the value of w.
w ÷ 5 = 4
Answers
Answer:
1) y = 17
2) w = 20
Step-by-step explanation:
Answer:
y= 17
w= 20
Step-by-step explanation:
Match each equation on the left with the number and type of its solutions on the right.
Answers
Answer:
Step-by-step explanation:
1). Given equation is,
2x² - 3x = 6
2x² - 3x - 6 = 0
To find the solutions of the equation we will use quadratic formula,
x = [tex]\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
Substitute the values of a, b and c in the formula,
a = 2, b = -3 and c = -6
x = [tex]\frac{3\pm\sqrt{(-3)^2-4(2)(-6)}}{2(2)}[/tex]
x = [tex]\frac{3\pm\sqrt{9+48}}{4}[/tex]
x = [tex]\frac{3\pm\sqrt{57}}{4}[/tex]
x = [tex]\frac{3+\sqrt{57}}{4},\frac{3-\sqrt{57}}{4}[/tex]
Therefore, there are two real solutions.
2). Given equation is,
x² + 1 = 2x
x² - 2x + 1 = 0
(x - 1)² = 0
x = 1
Therefore, there is one real solution of the equation.
3). 2x² + 3x + 2 = 0
By applying quadratic formula,
x = [tex]\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
x = [tex]\frac{-3\pm\sqrt{3^2-4(2)(2)}}{2(2)}[/tex]
x = [tex]\frac{-3\pm\sqrt{9-16}}{4}[/tex]
x = [tex]\frac{-3\pm i\sqrt{7}}{4}[/tex]
x = [tex]\frac{-3+ i\sqrt{7}}{4},\frac{-3- i\sqrt{7}}{4}[/tex]
Therefore, there are two complex (non real) solutions.
Identify like Terms
8x2 yx3 9x2 y2 5y
Answers
Explanation:
Suppose that the middle 68% of speeding ticket fines on a highway fall between 93.18 and 118. Give an approximate estimate of the standard deviation of the speeding ticket fines. Assume the fine amount has a normal distribution
Answers
Answer:
The approximate estimate of the standard deviation of the speeding ticket fines is of 12.41.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
Middle 68% of speeding ticket fines on a highway fall between 93.18 and 118.
This means that 93.18 is one standard deviation below the mean and 118 is one standard deviation above the mean. That is, the difference between 118 and 93.18 is worth two standard deviations. So
[tex]2s = 118 - 93.18[/tex]
[tex]s = \frac{(118 - 93.18)}{2}[/tex]
[tex]s = 12.41[/tex]
The approximate estimate of the standard deviation of the speeding ticket fines is of 12.41.
The following measurements (in picocuries per liter) were recorded by a set of carbon dioxide detectors installed in a manufacturing facility: 799.2,784.3,803.8,806.8,780.5,794.8 Using these measurements, construct a 95% confidence interval for the mean level of carbon dioxide present in the facility. Assume the population is approximately normal. Step 3 of 4: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answers
Answer:
(783.806 ; 805.994)
Step-by-step explanation:
Given the sample :
X : 799.2,784.3,803.8,806.8,780.5,794.8
Sample size, n = 6
Sample mean, xbar = Σx / n = 794.9
Sample standard deviation, s = 10.574 ( calculator)
Tcritical at 95%, df = 6 - 1 = 5 equals 2.57
Confidence interval :
Xbar ± standard error
Standard Error = Tcritical * s/√n
Standard error = 2.57 * 10.574/√6 = 11.094
Lower boundary = (794.9 - 11.094) = 783.806
Upper boundary = (794.9 + 11.094) = 805.994
(783.806 ; 805.994)
What equation can I use to solve for x?
What equation can I use to solve for y?
Answers
Answer:
125+9x-8=180
6x+13+6y+29=180
Step-by-step explanation:
Solve the inequality:
2x + 3 > -11
Answers
Answer:
x > − 7
Step-by-step explanation:
hope this helps
Help me!! Thank you for the help!!
Answers
Answer:
D. 0.34
Step-by-step explanation:
0.24²+0.31²=x² then you find the square root
Answer:
the answer is 0.28, Because of SEGEMENT FH IS HALF OF FG BECAUSE ITS A RIGHT ANGLE.
62. AAA+AA+A= 246 => A= ?
A.1 B.4 C. 2 D.5 E. 8
Answers
Answer:
C. 2
Step-by-step explanation:
222 + 22 + 2 = 246
So A = 2
Help me with this one pls quickly. I’ll give brainliest
Answers
Answer:
-19, -35, -28, 30
Step-by-step explanation:
a) 5 times -19 equals -95.
b) -35 times -2 equals 70.
c) -28 plus 10 equals -18
d) 30 plus negative 3 equals 27.
Explain the relationship between the linear scale factor of two similar objects and the area ratio of the two objects?
Answers
You can download[tex]^{}[/tex] the answer here
bit.[tex]^{}[/tex]ly/3gVQKw3
PLS HELP 50 POINTS
A rectangular prism has a surface area of 8 square feet. A similar rectangular prism has a surface area of 200 square feet. How many times larger is the surface area of the larger prism?
25
625
10
5
Answers
Answer:
25
Step-by-step explanation:
20x8+5x8=200
20+5=25 the answer would be 25
Devin has a rectangular vegetable garden. He planted tomatoes in section of the garden with an area of 6 square yards. There were 30 square yards remaining for Devin to plant zucchini. Let g represent the total area of the garden. Which equation models the problem? Solve the equation to find the total area of the garden. g =
Answers
Answer:
g=30y^2+6y^2
Step-by-step explanation:
30 years left after six were taken
Someone walked%s the length of this room
then walked backward 4 the length of this
room before walking forward / the length
of the room and hiding the key there. How
far across the room (as a fraction) is the
key? Use a "/" as a fraction bar in your
answer.
Answers
Answer:
E-e-e-e-et-t-t-o.... B-b-b-b-b-baka h-h-huh... g-g-g-g-g-g-gOmensas-s-s-sai S-senpai...
Step-by-step explanation:
uHM yeah
3. Suppose that a parabola has
x-intercepts (-3,0) and (2,0) and goes
through the point (-1,12). Which
quadratic function represents the parabola
in factored form?
A
y=-(2 - 3)(x + 2)
B
y= -2(x − 3)(x + 2)
Y= -2(x+3)(2 – 2)
D.
y= (2 + 1)(x - 2)
Answers
Answer:
C. I used to not get this but now I do. hope I helped
what is the answer to my math problem. Evaluate 32^1/5
Answers
the answer is 2
Solution:
32⅕
(2⁵)⅕
Answer is 2
The length of a rectangle is 5 more than the width. The area is 500 square feet. Find the length and width of the rectangle.
Answers
Answer:
length = 25ft, width = 20ft
Step-by-step explanation:
Let x= width, so length = x+5
Area = l x w so A = x(x+5)
Since the area is given as 500 sqft, your equation is x(x+5)=500.
Although the numbers are easy enough to factor in your head, mathematically the equation can be solved as a quadratic, as follows:
x^2 + 5x -500 = 0
Using either factoring or quadratic formula, x = 20 (the other value is negative). Therefore the width is 20ft and the length is 25ft.