Let R be a system consisting of rational expressions. Which operations are closed for R?
Answers
Answer:
D
Step-by-step explanation:A set is said to be closed under an operation when the application of the operation between any two elements of the set leads to an element that belongs to the same set. If a set is closed under an operation, it is said to have the closure property of that operation. When we combine two rational expressions by adding, subtracting, multiplying, or dividing, we get a rational expression. This pattern indicates that rational expressions are closed for all four operations.
Related Questions
Can you wiggle your ears? Use the students in your statistics class (or a group of friends) to estimate the percentage of people who can wiggle their ears. How can your result be thought of as an estimate for the probability that a person chosen at random can wiggle his or her ears? Comment: National statistics indicate that about 13% of Americans can wiggle their ears (Source: Bernice Kanner, Are You Normal?, St. Martin's Press, New York). The resulting relative frequency can be used as an estimate of the true probability of all Americans who can wiggle their ears. The resulting relative frequency can be used as an estimate of the true probability of all Americans who cannot wiggle their ears. The resulting relative frequency is the true probability of all Americans who can wiggle their ears. The resulting relative frequency cannot be used as an estimate of the true probability of all Americans who can wiggle their ears.
Answers
Answer:36
Step-by-step explanation:
Please help with this
Answers
The shape has 11 sides.
Using the angle formula for polygons:
The sum of all the interior angles is:
11-2 x 180 = 9 x 180 = 1,620 degrees.
For one angle divide the total by number of sides:
1620 / 11 = 147.27 which rounds to 147.2
The answer is D.
A recent survey asked 1200 randomly selected U.S. adults if they believe that the U.S. federal government is doing enough to keep U.S. elections safe from outside interference. After analyzing the results, the researchers were able to state that they are 95% confident that between 52.5% and 59.5% of all U.S. adults believe that the U.S. federal government is not doing enough to keep U.S. elections safe. Which statement BEST describes how to interpret these results
Answers
Complete Question
The complete question is shown on the first uploaded image
Answer:
The correct option is D
Step-by-step explanation:
From the question the question we are told that
The researchers were able to state that they are 95% confident that between 52.5% and 59.5% of all U.S. adults believe that the U.S. federal government is not doing enough to keep U.S. elections safe.
Generally a confidence interval states to what extent the chances of the true population is within the a given range
So the 95% confidence interval given in the question as 52.5% and 59.5% means that the chances of the true population mean being with this given range is 95%
So given that the the true population mean is within this range then it means that the population mean will be greater than 50%
So the statement that best describe and interprets this result is
The results show significant statistical support that most U.S. adults (over 50%) believe that the U. S. Federal government is not doing enough to keep U.S. election safe.
8) The perimeter of a rectangle is 20x2 + xy - 7y2 and one of it's sides is
7x2 - xy. Find the other side.
Answers
Answer:
3x^2 + 3xy/2 - 7xy^2/2
Step-by-step explanation:
So we know the perimeter is 20x^2 + xy - 7y^2,
To find any perimeter you need 2l + 2w = P so,
One of the sides is 7x^2 - xy
First plug in the values,
2(7x^2-xy) + 2w = 20x^2 + xy - 7y^2
Multiply,
14x^2-2xy + 2w = 20x^2 + xy - 7y^2
Subtract,
14x^2 - 2xy - 14x^2 + 2xy + 2w = 20x^2 + xy - 7y^2 - 14x^2 + 2xy
2w = 6x^2 + 3xy - 7y^2
w = 3x^2 + 3xy/2 - 7xy^2/2
Alex has to pay his car insurance twice a year. Each Payment is 312. How much money should Alex budget for his insurance each month?
Answers
312 • 2 = 624
Step 2:
624 divided by 12 months
Answer:
$52 a month
Answer:
$52
Step-by-step explanation:
$52. Since Alex pays for car insurance twice a year, divide the cost of each payment by 6, the number of months in half a year. This will tell you how much money Alex needs to set aside each month to cover his insurance costs.
312÷6=52
A standardized exam's scores are normally distributed. In a recent year, the mean test score was and the standard deviation was . The test scores of four students selected at random are , , , and . Find the z-scores that correspond to each value and determine whether any of the values are unusual. The z-score for is nothing. (Round to two decimal places as needed.) The z-score for is nothing. (Round to two decimal places as needed.) The z-score for is nothing. (Round to two decimal places as needed.) The z-score for is nothing. (Round to two decimal places as needed.) Which values, if any, are unusual? Select the correct choice below and, if necessary, fill in the answer box within your choice. A. The unusual value(s) is/are nothing. (Use a comma to separate answers as needed.) B. None of the values are unusual.
Answers
Answer:
The z-score for 1880 is 1.34.
The z-score for 1190 is -0.88.
The z-score for 2130 is 2.15.
The z-score for 1350 is -0.37.
And the z-score of 2130 is considered to be unusual.
Step-by-step explanation:
The complete question is: A standardized exam's scores are normally distributed. In recent years, the mean test score was 1464 and the standard deviation was 310. The test scores of four students selected at random are 1880, 1190, 2130, and 1350. Find the z-scores that correspond to each value and determine whether any of the values are unusual. The z-score for 1880 is nothing. (Round to two decimal places as needed.) The z-score for 1190 is nothing. (Round to two decimal places as needed.) The z-score for 2130 is nothing. (Round to two decimal places as needed.) The z-score for 1350 is nothing. (Round to two decimal places as needed.) Which values, if any, are unusual? Select the correct choice below and, if necessary, fill in the answer box within your choice. A. The unusual value(s) is/are nothing. (Use a comma to separate answers as needed.) B. None of the values are unusual.
We are given that the mean test score was 1464 and the standard deviation was 310.
Let X = standardized exam's scores
The z-score probability distribution for the normal distribution is given by;
Z = [tex]\frac{X-\mu}{\sigma}[/tex] ~ N(0,1)
where, [tex]\mu[/tex] = mean test score = 1464
[tex]\sigma[/tex] = standard deviation = 310
S, X ~ Normal([tex]\mu=1464, \sigma^{2} = 310^{2}[/tex])
Now, the test scores of four students selected at random are 1880, 1190, 2130, and 1350.
So, the z-score of 1880 = [tex]\frac{X-\mu}{\sigma}[/tex]
= [tex]\frac{1880-1464}{310}[/tex] = 1.34
The z-score of 1190 = [tex]\frac{X-\mu}{\sigma}[/tex]
= [tex]\frac{1190-1464}{310}[/tex] = -0.88
The z-score of 2130 = [tex]\frac{X-\mu}{\sigma}[/tex]
= [tex]\frac{2130-1464}{310}[/tex] = 2.15
The z-score of 1350 = [tex]\frac{X-\mu}{\sigma}[/tex]
= [tex]\frac{1350-1464}{310}[/tex] = -0.37
Now, the values whose z-score is less than -1.96 or higher than 1.96 are considered to be unusual.
According to our z-scores, only the z-score of 2130 is considered to be unusual as all other z-scores lie within the range of -1.96 and 1.96.
Factor: 2(4-y)-j(4-y)
Answers
Answer:
(2-j)(4-y)
Step-by-step explanation:
Factoring using grouping,
(2-j)(4-y)
Let f(x)=x+8 and g(x)= x2-6x-7 find f(g2)
Answers
Answer:
-7.
Step-by-step explanation:
g(x) = x^2 - 6x - 7
g(2) = 2^2 - 6(2) - 7
= 4 - 12 - 7
= -8 - 7
= -15
f(x) = x + 8
f(-15) = (-15) + 8
= 8 - 15
= -7
Hope this helps!
Solve the following equation using the square root property.
9x2 + 10 = 5
Answers
Solving Steps:
9x^2+10=5
Simplify- 81x+10=5
Subtract 10 from both sides- 81x +10 -10= 5 -10
Simplify- 81x= -5
Divide both sides by 81- 81x/81= -5/81
Simplify- X= -5/81
what is 12x^3-9x^2-4x+3 in factored form?
Answers
Answer: (3x^2-1)(4x-3)
============================
Work Shown:
Use the factor by grouping method
12x^3-9x^2-4x+3
(12x^3-9x^2)+(-4x+3)
3x^2(4x-3)-1(4x-3)
(3x^2-1)(4x-3)
y x1 x2
10 1 16
11 5 11
15 5 14
15 9 11
20 7 1
23 11 8
27 16 7
32 21 3
a. Using technology, construct a multiple regression model with the given data.
b. Interpret the meaning of the values for b1 and b2.
Answers
Answer:
ŷ = 0.964X1 - 0.336X2 + 13.066
b1 = 0.964 which is the unit change in the value of y when x1 changes.
b2 = - 0.336 which is the unit change in the value of y when x2 changes
Step-by-step explanation:
Y
10
11
15
15
20
23
27
32
X1
1
5
5
9
7
11
16
21
X2
16
11
14
11
1
8
7
3
The general form of a multiple regression equation is in form:
ŷ = b1x1 + b2x2 + c
Where,
ŷ = predicted or dependent variable
b1 and b2 = slope or gradient Coefficient for the independent or predictor variables x1 and X2 respectively.
c = intercept (constant)
Using the online multiple regression calculator, the model obtained by Inputting the values is written below:
ŷ = 0.964X1 - 0.336X2 + 13.066
Value of b1 = 0.964 which is the unit change in the value of y when x1 changes.
Value b2 = - 0.336 which is the unit change in the value of y when x2 changes
60feet to meters plaese with work
Answers
Answer:
60 Feet = 18.288 Meters
Step-by-step explanation:
foot = 12 inch = 0.3048 m
0.3047 × 60
18.288 meters
A maker of microwave ovens advertises that no more than 10% of its microwaves need repair during the first 5 years of use. In a random sample of 50 microwaves that are 5 years old, 12% needed repairs at a=.04 can you reject the makers claim that no more than 10% of its microwaves need repair during the first five years of use?
Answers
Answer:
We conclude that no more than 10% of its microwaves need repair during the first five years of use.
Step-by-step explanation:
We are given that a maker of microwave ovens advertises that no more than 10% of its microwaves need repair during the first 5 years of use.
In a random sample of 50 microwaves that are 5 years old, 12% needed repairs.
Let p = population proportion of microwaves who need repair during the first five years of use.
So, Null Hypothesis, [tex]H_0[/tex] : p [tex]\leq[/tex] 10% {means that no more than 10% of its microwaves need repair during the first five years of use}
Alternate Hypothesis, [tex]H_A[/tex] : p > 10% {means that more than 10% of its microwaves need repair during the first five years of use}
The test statistics that will be used here is One-sample z-test for proportions;
T.S. = [tex]\frac{\hat p-p}{\sqrt{\frac{p(1-p)}{n} } }[/tex] ~ N(0,1)
where, [tex]\hat p[/tex] = sample proportion of microwaves who need repair during the first 5 years of use = 12%
n = sample of microwaves = 50
So, the test statistics = [tex]\frac{0.12-0.10}{\sqrt{\frac{0.10(1-0.10)}{50} } }[/tex]
= 0.471
The value of z-test statistics is 0.471.
Now, at a 0.04 level of significance, the z table gives a critical value of 1.751 for the right-tailed test.
Since the value of our test statistics is less than the critical value of z as 0.471 < 1.751, so we have insufficient evidence to reject our null hypothesis as the test statistics will not fall in the rejection region.
Therefore, we conclude that no more than 10% of its microwaves need repair during the first five years of use.
Which equation is equivalent to StartRoot x EndRoot + 11 = 15?
Answers
Answer:
D [tex]\sqrt{x} +11=15[/tex]
Step-by-step explanation:
Edge 2020
For the given expression √x + 11 = 15 the value of x will be equal to 16.
What is an expression?
The mathematical expression combines numerical variables and operations denoted by addition, subtraction, multiplication, and division signs.
Mathematical symbols can be used to represent numbers (constants), variables, operations, functions, brackets, punctuation, and grouping. They can also denote the logical syntax's operation order and other properties.
Given that the expression √x + 11 =15. The expression will be solved as below,
√x + 11 =15
√x = 15 - 11
√x = 4
Squaring on both sides of the equation,
x = 4²
x = 16
To know more about an expression follow
https://brainly.com/question/25968875
#SPJ6
Chelsea played her tuba from 4:25 pm until 5:07
Answers
Answer:
42 minutes
Step-by-step explanation:
if you are asking how long it takes Chelsea to play her tuba then you do: 67 - 25 = 42
Answer:
Step-by-step explanation:
jhngjnh
Evaluating function expressions
-1•f(-8)-4•g(4)=
Answers
Answer: -7
Step-by-step explanation:
To find f(-8) look at the f function. Find the y value when x = -8
To find g(4) look at the g function. Find the y value when x = 3
Plug these values into the equation
-1 f(-8) - 4 f(4)
-1 (-5) - 4 (3)
5 - 12 = -7
Factor the expression completely. 6×3- 4×2 – 16x A. 0 B. 2x(3×2 – 2x – 8) C. 2x(3x + 4)(x – 2) D. 4x(2x + 1)(x – 4) E. 2x(2×2 + 7x – 4) ill give brainliest
Answers
Answer:
The answer is option CStep-by-step explanation:
6x³ - 4x² - 16x
To factorize the expression first factor out the GCF out
The GCF in the expression is 2x
That's
2x( 3x² - 2x - 8)
Next Factorize the terms in the bracket
To factorize write - 2x as a difference
that's
2x( 3x² + 4x - 6x - 8)
Factor out x from the expression
2x [ x( 3x + 4) - 6x - 8 ]
Next factor out - 2 from the expression
2x [ x ( 3x + 4) - 2( 3x + 4) ]
Factor out 3x + 4 from the expression
We have the final answer as
2x( 3x + 4)( x - 2)Hope this helps you
Which is a perfect square? 6 Superscript 1 6 squared 6 cubed 6 Superscript 5 What is the length of the hypotenuse, x, if (20, 21, x) is a Pythagorean triple
Answers
Answer:
Step-by-step explanation:
Hello, by definition a perfect square can be written as [tex]a^2[/tex] where a in a positive integer.
So, to answer the first question, [tex]6^2[/tex] is a perfect square.
(a,b,c) is a Pythagorean triple means the following
[tex]a^2+b^2=c^2[/tex]
Here, it means that
[tex]x^2=20^2+21^2=841=29^2 \ \ \ so\\\\x=29[/tex]
Thank you.
Answer:
Its B
Step-by-step explanation:
In the following equation, when x=3, what is the value of y? -4x + 3y = 12 A. 9 B. 3 C. 0 D. 8 PLZ HURRY IM TIMED WILL MARK BRAINLIEST
Answers
Answer:
[tex]\huge\boxed{y = 8}[/tex]
Step-by-step explanation:
-4x + 3y = 12
Given that x = 3
-4 (3) + 3y = 12
-12 + 3y = 12
Adding 12 to both sides
3y = 12+12
3y = 24
Dividing both sides by 3
y = 8
Answer:
y =8
Step-by-step explanation:
-4x + 3y = 12
Let x = 3
-4(3) +3y = 12
-12+3y = 12
Add 12 to each side
-12+12+3y =12+12
3y =24
Divide each side by 3
3y/3 = 24/3
y =8
Find the value of x.
Answers
Answer:
6x + 6 = 32
6x = 32 - 6
6x = 26
divide both sides by 6
6x/6 = 26/6
6x + 6 = 4.35
9x - 9 = 24
9x = 24 + 9
9x = 33
divide both sides by 9
9x/9 = 24/9
9x + 9 = 2.66
9x + 9 = 2.66
Answer: x=3
Step-by-step explanation:
[tex]\frac{32}{24} =\frac{4}{3} \\\\\frac{4}{3}=\frac{6x+6}{9x-9}\\ x=3[/tex]
solve for x: 5x+3+8x-4=90
Answers
Answer:
[tex]x = 7[/tex]
Step-by-step explanation:
We can solve the equation [tex]5x+3+8x-4=90[/tex] by isolating the variable x on one side. To do this, we must simplify the equation.
[tex]5x+3+8x-4=90[/tex]
Combine like terms:
[tex]13x - 1 = 90[/tex]
Add 1 to both sides:
[tex]13x = 91[/tex]
Divide both sides by 13:
[tex]x = 7[/tex]
Hope this helped!
Answer:
x = 7
Step-by-step exxplanation:
5x + 3 + 8x - 4 = 90
5x + 8x = 90 - 3 + 4
13x = 91
x = 91/13
x = 7
probe:
5*7 + 3 + 8*7 - 4 = 90
35 + 3 + 56 - 4 = 90
A nutrition laboratory tested 25 "reduced sodium" hotdogs of a certain brand, finding that the mean sodium content is 310 mg with a standard deviation of 36 mg.
Construct a 95% confidence interval for the mean sodium content of this brand of hot dog and interpret a 95% level of confidence. Show all work
Answers
Answer:
The 95% confidence interval is [tex]295.9 < \mu< 324.1[/tex]
A 95% level of confidence mean that there is 95% chance that the true population mean will be in this interval
Step-by-step explanation:
From the question we are told that
The sample size is [tex]n = 25[/tex]
The mean is [tex]\= x = 310 \ mg[/tex]
The standard deviation is [tex]\sigma = 36 \ mg[/tex]
Given that the confidence level is 95% then the level of significance is mathematically represented as
[tex]\alpha = 100 - 95[/tex]
=> [tex]\alpha = 5\%[/tex]
=> [tex]\alpha = 0.05[/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} } =Z_{\frac{0.05 }{2} } = 1.96[/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \frac{\sigma }{\sqrt{n} }[/tex]
substituting values
[tex]E = 1.96 * \frac{36 }{\sqrt{25} }[/tex]
[tex]E = 14.1[/tex]
The 95% level of confidence interval is mathematically represented as
[tex]\= x - E < \mu<\ \= x - E[/tex]
substituting values
[tex]310- 14.1 < \mu< 310+ 14.1[/tex]
[tex]295.9 < \mu< 324.1[/tex]
The 95% level of confidence mean that there is 95% chance that the true population mean will be in this interval
the temperature at which water freezes on the celsius scale is 0 degrees C. It freezes at 32 degrees F on the Fahrenheit scale, write opposites fo these two numbers as integers.
Answers
Answer:
If we have an integer number N, the opposite of N will be:
-1*N = -N.
Then, the opposite of 0°C is:
-1*0°C = 0°C.
The number 0 is it's own opposite.
And for 32F, the opposite is:
-1*32F = -32F
So, while the numbers 0°C and 32F physically represent the same thing (the same temperature), mathematically, they behave differently.
Solve 13x + 14 = 12x -5 (make sure to type the number only)
Answers
Answer:
x = -19
Step-by-step explanation:
13x + 14 = 12x - 5
subtract 12x from both sides
x + 14 = -5
subtract 14 from both sides
x = -19
Answer:
x= -19
Step-by-step explanation:
13x+14=12x−5
Subtract 12x from both sides.
13x+14−12x=−5
Combine 13x and −12x to get x.
x+14=−5
Subtract 14 from both sides.
x=−5−14
Subtract 14 from −5 to get −19
x=−19
Line k has a slope of 2/3. Find the slope of a line parallel to line k.
Answers
Answer:
We have to remember
slope = m
if the slope of line is parellel so it will be the same with other slope
m1= m2
2/3= 2/3
so the answer is 2/3
hope it helps ^°^
Answer:
2/3
Step-by-step explanation:
Parallel lines have the same slopes. Therefore,
[tex]m_{k} =m_{p}[/tex]
The slope of line k ([tex]m_{k}[/tex]) will be equal to the slope of the line parallel to k ([tex]m_{p}[/tex]).
We know that the slope of line k is 2/3.
[tex]m_{k}=\frac{2}{3}[/tex]
Therefore, the slope of the line parallel to line k is also 2/3.
[tex]\frac{2}{3}=m_{p}[/tex]
The slope of a line parallel to line k is 2/3.
Determine which is the appropriate approach for conducting a hypothesis test. Claim: The mean RDA of sodium is 2400mg. Sample data: n150, 3400, s550. The sample data appear to come from a normally distributed population.
Answers
Answer:
Use the student t distribution
Step-by-step explanation:
Here is the formula
t = (x - u) ÷(s/√N)
From the information we have in the question:
n = 150
s = 550
x = 3400
u = mean = 2400
= 3400 - 2400÷ 500/√150
= 1000/44.9
= 22.27
At 0.05 significance level, df = 149 so t tabulated will be 1.65.
We cannot use normal distribution since we do not have population standard deviationWe cannot use normal distribution since we do not have population standard deviationChisquare cannot be used since we are not testing for population varianceWe cannot use normal distribution since we do not have population standard deviationChisquare cannot be used since we are not testing for population varianceThe parametric or bootstrap method cannot be used either.Cybil flips a coin and rolls a fair number cube at the same time. What is the probability that she will toss tails and roll a number less than 3? A. 1/6 B. 1/3 C. 2/5 D. 1/2 Please include ALL work! <3
Answers
[tex]|\Omega|=2\cdot6=12\\|A|=1\cdot2=2\\\\P(A)=\dfrac{2}{12}=\dfrac{1}{6}[/tex]
Why would a linear function be an appropriate model?
Answers
Answer:
I know the answer
Step-by-step explanation:
Linear functions are those whose graph is a straight line. A linear function has the following form. y = f(x) = a + bx. A linear function has one independent variable and one dependent variable. The independent variable is x and the dependent variable is y.
Find the area of the shaded triangle below.
Answers
Answer:
A = 12 square units
Step-by-step explanation:
Area of a Triangle = base * height / 2
The triangle might look weird and doesn't look like it has a base, but if you look at the left side you see there is a straight line which means there is a base, so we flip the picture until we see that the flat line on the bottom or the base.
The base is 4 units.
To find the height, we don't need a straight line, we just need to see how the tall the triangle is, to do that you must start from the lowest point and count up to the highest point.
You now get 6 units.
A = bh/2
A = 4*6/2
A = 24/2
A = 12 square units
Which expression is equivaleny to 0.7 + p + 0.86p?
A.1 + 1.56p
B.p + 1.56
C.2.56p
D. -0.84p
Answers
Answer:
None of the above.
1.86p + 0.7
Step-by-step explanation:
Step 1: Write expression
0.7 + p + 0.86p
Step 2: Combine like terms
0.7 + 1.86p
None of those answer choices are correct unless you wrote the problem incorrectly.
